The DOI matches its Crossref record; 158 of the 158 references it cites were found in a registry or an index; none of the 103 sources its claims cite is checked for support yet.
Sex-Based Differences in Skeletal Muscle Kinetics and Fiber-Type Composition
Open accessAbstract
Previous studies have identified over 3,000 genes that are differentially expressed in male and female skeletal muscle. Here, we review the sex-based differences in skeletal muscle fiber composition, myosin heavy chain expression, contractile function, and the regulation of these physiological differences by thyroid hormone, estrogen, and testosterone. The findings presented lay the basis for the continued work needed to fully understand the skeletal muscle differences between males and females.
Overview
AI snapshot
Written from the paper’s full text.
TL;DR
This review summarizes sex-based differences in skeletal muscle fiber-type composition, myosin heavy chain expression, contractility, fatigue, and hormonal regulation by thyroid hormone, estrogen, and testosterone. It concludes that females generally have a higher prevalence of slower, more oxidative type-I/IIA fibers and greater endurance/recovery, while males tend to have faster contractile kinetics and greater fatigability.
Key findings
- More than 3,000 genes are differentially expressed between male and female skeletal muscle. In human vastus lateralis, female muscle has 35% more MyHC-I/β, 30% less MyHC-IIa, and 15% less MyHC-IIx mRNA than male muscle; type-I fibers account for 44% of biopsy area in women vs. 36% in men, while type-IIA fibers account for 34% in women vs. 41% in men.
- Contractile and fatigue differences are reported: mouse masseter maximal rate of force generation is higher in males (516 vs. 382 g/s), and relaxation is faster in males (41 vs. 48 ms). Endurance is lower in men than women in some studies (11 vs. 18 min; elbow flexor 829 s in males vs. 1,806 s in females), and in adductor pollicis force falls to ∼93% of maximum in women vs. 80% in men after <1 min of exercise.
- Hormonal regulation shows sex-specific effects. T3 treatment in rat soleus produces different fiber-type profiles in males (73% type-I/IIA, 26% type-I/IIAX) vs. females (37% type-I, 49% type-I/IIA, 6% type-I/IIAX). Ovariectomy reduces maximal isometric tetanic force from sham 180 mN to 168 mN, attenuated to 187 mN with estrogen; strong-binding myosin is 0.263 in OVX vs. 0.300 sham and 0.311 with estrogen.
- Testosterone-related morphology: in human vastus lateralis, type-I fibers are 19% larger, type-IIA fibers 59% larger, and type-IIX fibers 66% larger in men than women.
Methods
- Narrative review of sex-based differences in skeletal muscle fiber composition, myosin heavy chain expression, contractile function, and regulation by thyroid hormone, estrogen, and testosterone.
- Evidence is synthesized from cited human and animal studies, including human vastus lateralis biopsies and rodent, rabbit, guinea pig, and canine muscle models; no new primary data are presented.
- Main analysis is literature synthesis, with summary tables for fiber-type expression, baseline contractility, thyroid hormone effects, and ERβ-null mouse data.
Limitations
- The paper states that studies investigating sex-based differences in muscle fiber type are somewhat limited, that experimental models often study only males because sex is thought to confound results, and that further investigations are needed; it also notes that one or two genes cannot explain all sex differences.
- Evident from the text: this is a narrative review without a systematic search or meta-analysis, and findings are heterogeneous across species, muscles, ages, and methods; some cited results are contradictory, such as T3 effects on shortening velocity, and some mechanisms remain uninvestigated, including calcium storage capacity after ovariectomy.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
82 Not checked yet · 25 Own interpretation · 1 No basis given
In the paper
“Additionally, all of the fibers measured in men have significantly larger cross-sectional areas (CSA) compared with women as normalized to biopsy section area (89).”
What the sources say
- Not checked yetcites [89] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
None of the sources cited for this claim have been checked yet.
In the paper
“Studies on chemically skinned human fibers reveal that MyHC isoform composition is the key determinant of muscle fiber contractile velocity and rate of force development (11, 72).”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Although studies investigating sex-based differences in muscle fiber type are somewhat limited, there is also evidence of sexual dimorphisms with respect to muscle fiber-type composition (Table 2).”
What the sources say
- Not checked yetcites Table 2
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The difference in CSA seems likely to be due to the overall greater mass in males compared with females since the increase in CSA is nearly proportional to the differences in mass.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Previous studies have identified over 3,000 genes that are differentially expressed in male and female skeletal muscle.”
- Also stated in: § Abstract · plain
“More than 3,000 genes have been identified as being differentially expressed between male and female skeletal muscle (96).”
What the sources say
- Not checked yetcites [96] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § Abstract · plain
In the paper
“Although evidence suggests that maximum unloaded shortening velocity is not different between young male and female fibers (25), sex-based differences are seen during fatigue recovery and endurance testing (Table 3).”
What the sources say
- Not checked yetcites [25] source
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Analysis of tetanic force in the mouse masseter shows no significant differences between the sexes on force production (22).”
What the sources say
- Not checked yetcites [22] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Generally, male muscles are more fatigable than female muscles.”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: unclear — It is unclear why the paper says it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Fiber-type composition and contractile function can be altered by the presence or removal of specific hormones.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Skeletal muscle is an estrogen-responsive tissue such that estrogen receptor (ER) mRNA and protein levels change with circulating estrogen levels (7).”
What the sources say
- Not checked yetcites [7] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- It may state two separate claims as one. 63
- Probably not a substantial claim. 9
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“For example, MyHC-IIa expression is higher in males vs. females in the soleus (58% in males vs. 36% in females) and tibialis anterior (TA) (39% in males vs. 25% in females), whereas in the plantaris, IIa expression is higher in females (37%) than in males (16%).”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“The mouse masseter is composed of high numbers of IIX fibers in both sexes; however, there are threefold fewer IIB fibers and more IIA fibers in females compared with males (27).”
What the sources say
- Not checked yetcites [27] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Analysis of mRNA from both male and female vastus lateralis biopsies by microarray shows (when normalized to α-actinin) that the female muscle has 35% more MyHC-I/β, 30% less MyHC-IIa, and 15% less MyHC-IIx mRNA than the corresponding male muscle (96).”
What the sources say
- Not checked yetcites [96] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“There are 11 myosin heavy chain (MyHC) genes that encode different myosin isoforms in mammals (77).”
What the sources say
- Not checked yetcites [77] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Type-I fibers account for 36% of the total biopsy area in men and 44% in women, whereas type-IIA fibers account for 41% in men and only 34% in women (89).”
What the sources say
- Not checked yetcites [89] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Functionally, MyHC isoform expression directly affects muscle fiber-type contractile velocity via myosin ATPase activity (74), with relative velocities of I < IIA < IIX < IIB (73, 74).”
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In contrast, human skeletal muscle does not express MyHC-IIb protein, a phenomenon that appears to be, at least in part, due to a reduction in the activity of the human MyHC-IIb promoter region (37).”
What the sources say
- Not checked yetcites [37] source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Overall, in this analysis, the average MyHC isoform percentages in the male vastus lateralis are IIx (20%), IIa (46%), and I (34%), whereas the females samples are IIx (23%), IIa (36%), and I (41%) (89).”
What the sources say
- Not checked yetcites [89] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Overall, evidence to date suggests that skeletal muscle fiber-type composition is dependent on species, anatomical location/function, and sex.”
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Male rabbit masseter is comprised of nearly 80% type-IIA fibers, whereas the female masseter contains only ∼50% (28).”
What the sources say
- Not checked yetcites [28] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Treatment of euthyroid animals with T3 induces hyperthyroidism, producing a reversible slow-to-fast MyHC isoform transition from I → IIa → IIx → IIb (for review, see Ref. 78).”
What the sources say
- Not checked yetcites [78] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These studies suggest a potential role for T3 in skeletal muscle contractility and in sex-based differences that may exist in the response to changing T3 levels but point to the need for further investigations.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“In fact, hormonal regulation of skeletal muscle development and contractility are well documented (29, 70).”
boosted- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
In the paper
“Endurance is longer in women (15 min) compared with men (8 min), and after reaching exhaustion, recovery occurs faster in women than in men (31).”
What the sources say
- Not checked yetcites [31] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“T3 treatment in euthyroid animals leads to a conversion from IIA to IIB fibers in the EDL of young and old female rats vs. no transition in males (52).”
What the sources say
- Not checked yetcites [52] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Thyroid hormone (T3) can regulate MyHC gene expression (42).”
What the sources say
- Not checked yetcites [42] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These studies suggest that force generation and relaxation are faster during fatigue in men compared with women, whereas endurance is higher and recovery is quicker in women than in men.”
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“During menopause, the decline in estrogen levels is paralleled with a slight increase in injury risk and a decline in lean body mass (9).”
What the sources say
- Not checked yetcites [9] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Specifically, after treatment with T3, male rat soleus muscle expresses 73% type-I/IIA and 26% type-I/IIAX of the total fibers, whereas females express 37% type-I, 49% type-I/IIA, and only 6% type-I/IIAX fibers (101).”
What the sources say
- Not checked yetcites [101] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Hypothyroid females appear to have a higher proportion of type-II fibers compared with hypothyroid males; however, type-II fiber atrophy occurs in hypothyroid female patients but not in males (63).”
What the sources say
- Not checked yetcites [63] source
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Four weeks of T3 treatment induces an increase in type-IIA fibers and a downregulation of type-I fibers in male and female rat soleus muscle (57, 101).”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Overall, the increase in IIX content from the type-I/IIAX fibers is greater in young T3-treated males (21%) than females (10%), and the upregulation of IIA is greater in young females (43%) than in young males (27%) (101).”
What the sources say
- Not checked yetcites [101] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“After intermittent bouts of isometric contraction (5 s on and 5 s off) in the adductor pollicis muscle, women fatigue more slowly and to a smaller degree than men (31).”
What the sources say
- Not checked yetcites [31] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In another study of euthyroid animals, treatment with T3 induces expression of IIX in the soleus of aged male rats (4–15%), whereas there is no detectable IIX in females at any age (52).”
What the sources say
- Not checked yetcites [52] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These studies highlight the differences in fiber-type conversion as it relates to sex and pinpoints the differences in IIx expression in males and females.”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Animal models of low estrogen levels, which occur after ovariectomy (OVX), reveal an increase in overall body mass and in the mass of individual muscles (68).”
What the sources say
- Not checked yetcites [68] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Although forces exerted by both young men and women are not significantly different, endurance is lower for men than for women (11 vs. 18 min) (39).”
What the sources say
- Not checked yetcites [39] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“OVX leads to an increase in overall body weight and muscle weight (68), and a 70% increase in ERα mRNA with no change in ERβ mRNA (7).”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Estrogen has been shown to influence fiber size, overall muscle weight, muscle regeneration, and contractility, and to induce minimal changes in fiber-type distribution.”
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Overall, ERβ deletion increases the contractile time and decreases the speed of contractile kinetics in both males and females.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“This decline in regenerative capacity is thought to be directly related to findings that estrogen is associated with maintenance of muscle strength in pre- and postmenopausal women (69) and suggests a role for ERs in skeletal muscle maintenance (64, 84, 85, 88).”
What the sources say
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“The fraction of strong binding myosin in OVX muscle is 0.263 or ∼15% lower than baseline (67, 68). Following estrogen treatment, the fraction of strongly bound myosin increases to 0.311, which is indistinguishable from sham levels (0.300) (67).”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Relaxation time during a basic contraction in the soleus is significantly shorter in wild-type males (104 ms) than in females (158 ms) and in null males (104 ms) compared with null females (191 ms).”
What the sources say
- Not checked yetcites [33] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Because of the OVX-induced decrease in tetanic force, which requires rapid replenishment and utilization of calcium stores, and the increase in fiber diameter, which could compensate for a decline in calcium sensitivity, calcium handling and sensitivity may be playing a role in the regulation of contractile differences in samples with and without estrogen.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. It may state two separate claims as one.
In the paper
“Ronkainen et al. (76) found that HRT is associated with better mobility, greater muscle power, and favorable body and muscle composition in women ages 54–62 (76).”
What the sources say
- Not checked yetcites [76] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Analysis of contractile function in OVX mice reveals a significant decrease in maximal isometric tetanic force from sham levels (180 mN) to 168 mN (67, 68). This decline is attenuated to 187 mN with estrogen supplementation (67).”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the studies referenced in the previous sections, there is no change in MyHC isoform expression or overall muscle fiber-type composition, but there are estrogen-related changes in fiber-type diameter, muscle size, contractility, and the actin-myosin interaction.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In rat soleus and EDL muscles, OVX leads to a slight increase in the mean fiber diameter of type-I, -IIA, and -IIB fibers. Estrogen supplementation decreases fiber diameter in all fiber types in both the soleus and EDL significantly from OVX levels to below baseline levels (90).”
What the sources say
- Not checked yetcites [90] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In male and female vastus lateralis muscle, expression of ERα mRNA is 180-fold higher than ERβ, with no significant difference in expression levels between males and females (98).”
What the sources say
- Not checked yetcites [98] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“OVX induces a reduction in time to peak tension and increases time to 50% relaxation in rats, whereas estrogen replacement reverses the OVX-induced reduction in peak tension (62).”
What the sources say
- Not checked yetcites [62] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Skeletal muscle expresses two forms of ERs (α and β), and the effects of estrogen are mediated, in part, through these receptors (14, 21, 56, 98).”
What the sources say
plainconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Studies on muscle repair following exercise-induced injury highlight a sex-based difference in which higher levels of muscle creatine kinase (indicative of injury) are observed in male than in female rats following injury. Following OVX, levels of muscle creatine kinase in females are similar to levels in injured males (3, 4, 8).”
What the sources say
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“As stated previously, there is no sexually dimorphic expression in either ERα or ERβ in skeletal muscle (98).”
What the sources say
- Not checked yetcites [98] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Following a fatiguing protocol on soleus and EDL muscle, force decreases less in ERβ−/− males than in wild-type males, whereas the reverse is true for females, suggesting a role for ERβ knockout in enhancing endurance in males and reducing endurance in females (33).”
What the sources say
- Not checked yetcites [33] source
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Recent studies suggest a beneficial role for hormone replacement therapy (HRT), supplementation with estrogen and progesterone, and the induction of pathways by which estrogen can aide in skeletal muscle maintenance and repair (71).”
What the sources say
- Not checked yetcites [71] source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“ERα-null mice have a decreased muscle regenerative capacity following injury, as evidenced by small myofibers and centrally located nuclei (50).”
What the sources say
- Not checked yetcites [50] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Taken together, these findings on estrogen and the ER-mediated regulation of the contractile response and fiber-type distribution suggest a role for estrogen and its receptors in contractile maintenance and function, with a differential effect of estrogen in males vs. females.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In mice, castration produces a decrease in body weight, which is attenuated with testosterone supplementation, and although overall muscle weight increases, the fiber CSA of the soleus and TA do not significantly change (6).”
What the sources say
- Not checked yetcites [6] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“With advancing age, testosterone levels drop, and testosterone deficiency is associated with early death, primarily from cardiovascular disease, a decrease in muscle mass and/or strength, and sexual dysfunction (46).”
What the sources say
- Not checked yetcites [46] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“ARs are widely expressed in myoblasts, myofibers, and motoneurons in both males and females (17, 100), and testosterone injected into the masseter of female guinea pigs leads to an increase in fiber size (35).”
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Testosterone is a highly studied androgen that is associated with an increase in muscle mass (66, 83).”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Testosterone has been shown to induce its effects through binding to intracellular androgen receptors (ARs) (34), which then regulate gene transcription (18, 81).”
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
In the paper
“Analysis of fiber-type distribution in hypogonadal males vs. females reveals no significant changes in type-I, -IIA, -IIX, or -IIB fibers in gastrocnemius muscle or in type-I or -IIA fibers in the soleus (79).”
What the sources say
- Not checked yetcites [79] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Additionally, in AR-null males, force production decreases in fast-twitch fibers, whereas fatigue resistance increases in slow-twitch fibers to levels similar to wild-type females (59).”
What the sources say
- Not checked yetcites [59] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In mice, castration produces a decrease in body weight, which is attenuated with testosterone supplementation, and although overall muscle weight increases, the fiber CSA of the soleus and TA do not significantly change (6).”
What the sources say
- Not checked yetcites [6] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Additionally fiber-type distribution of the gastrocnemius is relatively unchanged from wild-type mice, with I < IIX < IIA < IIB being the relative contribution of each fiber-type in males and females (79).”
What the sources say
- Not checked yetcites [79] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“As mentioned earlier, studies of vastus lateralis biopsies show fiber-type CSA to be larger in men than in women. Specifically, type-I fibers are 19% larger, type-IIA fibers are 59% larger, and type-IIX fibers are 66% larger in men than in women (normalized to total biopsy section analyzed) (89).”
What the sources say
- Not checked yetcites [89] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These anabolic effects of testosterone are well characterized and provide the catalysts for further investigation of the response of muscle fiber-type composition to testosterone deficiency and supplementation in males and females.”
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: fails — It may be too vague to check against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. It may be too vague to check against evidence. The paper may give no reason why it holds. It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“During fatigue, where females typically have greater endurance, ERβ elimination decreases the endurance in the female and enhances endurance in the male.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Testosterone supplementation leads to an increase in muscle mass and a decrease in fat content in hypogonadal men (13).”
What the sources say
- Not checked yetcites [13] Brodsky IG, 1996, J Clin Endocrinol Metab
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“GRB10 knockout in male and female mice produces an increase in muscle weight and a decrease in body fat percentage and thus enhances muscularity (86).”
What the sources say
- Not checked yetcites [86] source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Testosterone deficiency leads to a decline in body mass, a decrease in fast-twitch fiber diameter, a conversion to slow-twitch fibers, and enhanced fatigue resistance in males but not females.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In this study, the authors focus on two particular genes that are upregulated in women compared with men and that are known to code for proteins that are in signaling pathways of growth factors known to regulate muscle mass: growth factor receptor-bound protein 10 (GRB10) and activin receptor type-2A (ACVR2A).”
What the sources say
- Not checked yetcites [96] source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Although thyroid hormone induces a conversion from slow to fast fibers and increases contractile velocity, sex-specific hormones estrogen and testosterone are implicated in skeletal muscle growth, fiber size, and minimally in contractile function.”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Sex-based differences in skeletal muscle fiber-type composition and function are apparent in numerous species and are present in specific anatomical locations.”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“There is a prevalence of slower type-I and -IIA fibers in females compared with males that parallels the lower contractile velocity in females compared with males.”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: unclear — It is unclear why the paper says it holds.
It may state two separate claims as one.
- Rests on an assumption: In adult mammalian muscle, the four main MyHC isoforms (MyHC-I, -IIa, -IIx, and -IIb) increase in contractile speed in that order.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Because aromatase converts testosterone to estrogen (60), testosterone can induce its effects via either ERs or ARs, thus this contractile effect is thought to be mediated by the activation of ERs.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper relies on this without support.
Sex is often thought to confound results in experimental models, so usually only males are studied.
“This is often the case in experimental models where sex is thought to confound results and therefore usually only males are studied.”
The paper relies on this without support.
A strong actin-myosin bond produces a greater force.
“Since a strong actin-myosin bond will produce a greater force, this has been measured in muscles with and without estrogen manipulation.”
The paper relies on this without support.
In adult mammalian muscle, the four main MyHC isoforms (MyHC-I, -IIa, -IIx, and -IIb) increase in contractile speed in that order.
“There are four main MyHC isoforms present in adult mammalian muscle (MyHC-I, -IIa, -IIx, and -IIb), which increase in contractile speed in the presented order.”
The paper relies on this without support.
Thyroid hormone induces a conversion from slow to fast fibers and increases contractile velocity.
“Although thyroid hormone induces a conversion from slow to fast fibers and increases contractile velocity, sex-specific hormones estrogen and testosterone are implicated in skeletal muscle growth, fiber size, and minimally in contractile function.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“Many of these physiological factors differ significantly between biological males and females as a result of genetic differences and androgen-directed development of secondary sex characteristics [3, 4].”
From Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage (2021) · cites this paper as [3]
Experimental — accuracy not yet measuredThe check wasn’t confident either way, so it gives no verdict — never disputed.
In the citing paper
“superior cardiovascular and respiratory function, with larger blood and heart volumes, higher hemoglobin concentration, greater cross-sectional area of the trachea and lower oxygen cost of respiration [3, 4, 39, 40].”
From Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage (2021) · cites this paper as [3]
Experimental — accuracy not yet measured
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Abstract
“Hypothyroidism produces a lower type-II fiber percentage in male and female patients compared with healthy patients (63).”
§ Abstract
“Hypothyroidism in humans ↑ Type-II ↑↑ Type-II 64”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Abstract
“Relaxation time during a basic contraction in the soleus is significantly shorter in wild-type males (104 ms) than in females (158 ms) and in null males (104 ms) compared with null females (191 ms).”
§ Abstract
“Relaxation time (soleus) 100.4 ms 158.2 ms 104.0 ms 191.4 ms”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Abstract
“In the studies referenced in the previous sections, there is no change in MyHC isoform expression or overall muscle fiber-type composition”
§ Abstract
“However, in the mouse plantaris muscle, OVX does lead to a reduction in the relative amount of type-IIX fibers from 38% in sham animals to 33% (70). Supplementation with estrogen increases the type-IIX percentage composition in the plantaris back to 42% (70).”
Citations
Cites
Calcium's Role in Mechanotransduction during Muscle Development
Damm, T. B., & Egli, M. (2014) · Cellular Physiology and Biochemistry · doi:10.1159/000356667 · Cited by 14,552
The functions of animal microRNAs
Ambros, V. (2004) · Nature · doi:10.1038/nature02871 · Cited by 10,728
Spinal and Supraspinal Factors in Human Muscle Fatigue
Gandevia, S. C. (2001) · Physiological Reviews · doi:10.1152/physrev.2001.81.4.1725 · Cited by 3,855
Fiber Types in Mammalian Skeletal Muscles
Schiaffino, S., & Reggiani, C. (2011) · Physiological Reviews · doi:10.1152/physrev.00031.2010 · Cited by 3,022
Policy: NIH to balance sex in cell and animal studies
Clayton, J. A., & Collins, F. S. (2014) · Nature · doi:10.1038/509282a · Cited by 1,816
Generation and reproductive phenotypes of mice lacking estrogen receptor β
Krege, J. H., Hodgin, J. B., Couse, J. F., Enmark, E., Warner, M. N., Mahler, J. F., Sar, M., Korach, K. S., Gustafsson, J.-Α., & Smithies, O. (1998) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.95.26.15677 · Cited by 1,717
Molecular diversity of myofibrillar proteins: gene regulation and functional significance
Schiaffino, S., & Reggiani, C. (1996) · Physiological Reviews · doi:10.1152/physrev.1996.76.2.371 · Cited by 1,545
mTOR controls mitochondrial oxidative function through a YY1–PGC-1α transcriptional complex
Cunningham, J. T., Rodgers, J. T., Arlow, D. H., Vazquez, F., Mootha, V. K., & Puigserver, P. (2007) · Nature · doi:10.1038/nature06322 · Cited by 1,488
Peroxisome proliferator-activated receptor a target genes
Mandard, S., M�ller, M., & Kersten, S. (2004) · Cellular and Molecular Life Sciences · doi:10.1007/s00018-003-3216-3 · Cited by 1,222
Vega, R. B., Huss, J. M., & Kelly, D. P. (2000) · Molecular and Cellular Biology · doi:10.1128/mcb.20.5.1868-1876.2000 · Cited by 1,195
Research works printed but not linked: 3
- Brodsky IG, 1996, J Clin Endocrinol Metab, 81, 3469
- MacIntosh BR, 2003, News Physiol Sci, 18, 222
- Maggiolini M, 1999, Cancer Res, 59, 4864
Cited by
Sorted by citations
Items 501–519 of 519
Miyazaki, F. A. L., Cruz, V. D., Furlan, C. C., Freire, A. R., Prado, F. B., Rossi, A. C., & Ferreira-Pileggi, B. C. (2026) · Cureus · doi:10.7759/cureus.113163
McManus, L., Scriney, M., & Egan, B. (2026) · International Journal of Sport Nutrition and Exercise Metabolism · doi:10.1123/ijsnem.2026-0098
Zhao, H., Cho, Y., Schnorenberg, A. J., Slavens, B. A., & Peterson, C. (2026) · Journal of Electromyography and Kinesiology · doi:10.1016/j.jelekin.2026.103197
Alaei, P., Larocque, K. A., Kim, C., & Jakobi, J. M. (2026) · SSRN Electronic Journal · doi:10.2139/ssrn.7451193
Ahn, T. R., Lee, K. H., Yoon, Y. S., Lee, J. H., & Lee, J. (2026) · British Journal of Radiology · doi:10.1093/bjr/tqag190
Tornero-Aguilera, J. F., Lozano-Meca, J. A., López‐Moreno, M., Sancho-Haro, E. S., Muñoz-López, M., Baz-Valle, E., López-Gil, J. F., Yáñez-Sepúlveda, R., & Clemente‐Suárez, V. J. (2026) · Experimental Physiology · doi:10.1113/ep094042
Takei, N., 邑木, 隆., Girard, O., Hatta, H., & Takahashi, Y. (2026) · European Journal of Sport Science · doi:10.1002/ejsc.70244
Vega-Monzó, L., Ranchal‐Sánchez, A., Baena-González, R., Durán-López, N., & Jurado‐Castro, J. M. (2026) · Scientific Reports · doi:10.1038/s41598-026-65495-4 · Cited by 1
Xue, H., Kang, M., Huang, J., Wang, X., Lai, X., Ma, Z., Xiang, Q., Tian, H., Guo, X., Li, Y., et al. (2026) · Frontiers in Medicine · doi:10.3389/fmed.2026.1878659
Peleg, S., Ravina, O., Shemy, E., & Ayalon, M. (2026) · Muscles · doi:10.3390/muscles5040072
Caspary-Isar, A., Jeanfavre, M., Kemp, O., Leff, G., Rahman, M., & Huddleston, B. S. (2026) · Sports · doi:10.3390/sports14100432
Herrera-Amante, C. A., Sepulveda, R. A. Y., Hoyos-Flores, J. R., García-Carrillo, E., Montenegro-Espinosa, J. A., Quiroz-Cárdenas, F., Becerra-Patiño, B. A., & López‐Gil, J. F. (2026) · Sports · doi:10.3390/sports14100444
Lee, W., Knoll, E., Pennartz, K. J., Sprick, J. D., & Keller, J. L. (2026) · Frontiers in Physiology · doi:10.3389/fphys.2026.1895045
Giacomello, E., Giraudi, P. J., Rosso, N., Gazzin, S., Tiribelli, C., & Toniolo, L. (2026) · Nutrients · doi:10.3390/nu18203354
Teodoro, R. C., Guimarães, M. P., Manoel, F. D. A., da Silva, S. F., & de Abreu, W. C. (2026) · Nutrition and Health · doi:10.1177/02601060261497497
Özdemir, B. T. (2026) · Özgür Yayınları eBooks · doi:10.58830/ozgur.pub1531.c6189
Timing the effort: Chronobiological drivers of skeletal muscle adaptation and metabolic health
Aykora, E., Erbil, G., & Aykora, D. (2026) · Chronobiology International · doi:10.1080/07420528.2026.2750361
Lusi, S., Carnicelli, G., Quaglia, A., Carimati, G., Volpi, P., Francone, M., Balzarini, L., & Magarelli, N. (2026) · Sports Health A Multidisciplinary Approach · doi:10.1177/19417381261492942
Metadata
- Authors
- Haizlip, K. M., Harrison, B. C., & Leinwand, L. A.
- Affiliations
- University of Colorado Boulder (US)
- Corresponding author
- Leinwand, L. A.
- Venue
- Physiology
- Publisher
- American Physiological Society
- Published
- 2015-01
- Volume
- 30
- Issue
- 1
- Pages
- 30-39
- ISSN
- 0886-1714 (ISSN-L)
- 1548-9213
- 1548-9221
- PMC
- PMC4285578
- OpenAlex
- W2097561994
- Semantic Scholar
- b290b0c3482c23b4612ebb91c3677997d764978e
- Cited by
- 521
- References
- 157
- Citations by year
- 2026: 52 · 2025: 79 · 2024: 89 · 2023: 65 · 2022: 69 · 2021: 49 · 2020: 37 · 2019: 41 · 2018: 20 · 2017: 8 · 2016: 7 · 2015: 4
- FWCI
- 1.25
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Physiology (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Heart, Lung, and Blood Institute (T32HL007822)
- National Institute of General Medical Sciences (GM-029090-30A1S1, GM-29090-31, R01GM029090)
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (K01AR055676)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Muscle Physiology and Disorders
- Health Sciences › Nursing › Nutrition and Dietetics › Muscle metabolism and nutrition
- Health Sciences › Medicine › Physiology (medical) › Cardiovascular and exercise physiology
- Keywords
- sex differences, skeletal muscle, muscle fiber composition, myosin heavy chain, muscle contractility, thyroid hormones, estrogen, testosterone, gene expression
- MeSH terms
- Animals, Female, Humans, Kinetics, Male, Muscle Contraction, Sex Characteristics, Thyroid Hormones, Muscle Fibers, Skeletal, Myosin Heavy Chains
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-10-09, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-09 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
