Contrasts in muscle and myofibers of elite male and female bodybuilders

1989 ◽  
Vol 67 (1) ◽  
pp. 24-31 ◽  
Author(s):  
S. E. Alway ◽  
W. H. Grumbt ◽  
W. J. Gonyea ◽  
J. Stray-Gundersen
Keyword(s):  
Lean Body Mass ◽  
Body Mass ◽  
Biceps Brachii ◽  
Body Height ◽  
Type I ◽  
Type Ii ◽  
Cross Sectional ◽  
Fiber Area ◽  
Fiber Number ◽  
Muscle Cross Sectional Area

Muscle cross-sectional area (CSA), fiber area, and fiber number were determined from the biceps brachii of eight elite male bodybuilders (MB) and five elite female bodybuilders (FB) who had similar training characteristics. Biceps CSA was obtained from computer tomographic scanning and corrected for noncontractile tissue. Biceps CSA was twofold greater in MB relative to FB and strongly correlated to lean body mass (R = 0.93). Biceps CSA expressed per kilogram lean body mass (LBM) or per centimeter body height (BH) was 35% greater in MB compared with FB. Most of the gender difference in muscle CSA was because of greater absolute mean fiber areas in MB (9,607 microns2) relative to FB (5,386 microns2); however, MB also had a significantly greater population of small type II fibers (less than 2,000 microns2) compared with FB. Type II fiber area/LBM averaged 1.6-fold greater in MB compared with FB; however, type I fiber area/LBM was similar between groups. Biceps CSA was positively correlated to fiber CSA (R = 0.75) and fiber number (R = 0.55). This suggests that adaptations to resistance training may be complex and involve fiber hypertrophy and fiber number (e.g., proliferation). Alternatively, since the muscle characteristics before training are not known, these apparent adaptations might be genetically determined attributes.

scholarly journals Reduced Appendicular Lean Body Mass, Muscle Strength, and Size of Type II Muscle Fibers in Patients with Spondyloarthritis versus Healthy Controls: A Cross-Sectional Study

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Kristine Røren Nordén ◽  
Hanne Dagfinrud ◽  
Amund Løvstad ◽  
Truls Raastad
Keyword(s):  
Body Composition ◽  
Muscle Strength ◽  
Lean Body Mass ◽  
Body Mass ◽  
Muscle Fibers ◽  
Type I ◽  
Healthy Controls ◽  
Type Ii ◽  
Mineral Density ◽  
Cross Sectional

Introduction. The purpose of this study was to investigate body composition, muscle function, and muscle morphology in patients with spondyloarthritis (SpA).Methods. Ten male SpA patients (mean ± SD age39±4.1years) were compared with ten healthy controls matched for sex, age, body mass index, and self-reported level of physical exercise. Body composition was measured by dual energy X-ray absorptiometry. Musculus quadriceps femoris (QF) strength was assessed by maximal isometric contractions prior to test of muscular endurance. Magnetic resonance imaging of QF was used to measure muscle size and calculate specific muscle strength. Percutaneous needle biopsy samples were taken fromm. vastus lateralis.Results. SpA patients presented with significantly lower appendicular lean body mass (LBM) (p=0.02), but there was no difference in bone mineral density, fat mass, or total LBM. Absolute QF strength was significantly lower in SpA patients (p=0.03) with a parallel trend for specific strength (p=0.08). Biopsy samples from the SpA patients revealed significantly smaller cross-sectional area (CSA) of type II muscle fibers (p=0.04), but no difference in CSA type I fibers.Conclusions. Results indicate that the presence of SpA disease is associated with reduced appendicular LBM, muscle strength, and type II fiber CSA.

Muscle fiber number in biceps brachii in bodybuilders and control subjects

1984 ◽  
Vol 57 (5) ◽  
pp. 1399-1403 ◽  
Author(s):  
J. D. MacDougall ◽  
D. G. Sale ◽  
S. E. Alway ◽  
J. R. Sutton
Keyword(s):  
Muscle Fiber ◽  
Biceps Brachii ◽  
Cross Sectional Area ◽  
Muscle Size ◽  
Sectional Area ◽  
Cross Sectional ◽  
Trained Subjects ◽  
Fiber Area ◽  
Muscle Cross Sectional Area

Muscle fiber numbers were estimated in vivo in biceps brachii in 5 elite male bodybuilders, 7 intermediate caliber bodybuilders, and 13 age-matched controls. Mean fiber area and collagen volume density were calculated from needle biopsies and muscle cross-sectional area by computerized tomographic scanning. Contralateral measurements in a subsample of seven subjects indicated the method for estimation of fiber numbers to have adequate reliability. There was a wide interindividual range for fiber numbers in biceps (172,085–418,884), but despite large differences in muscle size both bodybuilder groups possessed the same number of muscle fibers as the group of untrained controls. Although there was a high correlation between average cross-sectional fiber area and total muscle cross-sectional area within each group, many of the subjects with the largest muscles also tended to have a large number of fibers. Since there were equally well-trained subjects with fewer than normal fiber numbers, we interpret this finding to be due to genetic endowment rather than to training-induced hyperplasia. The proportion of muscle comprised of connective and other noncontractile tissue was the same for all subjects (approximately 13%), thus indicating greater absolute amounts of connective tissue in the trained subjects. We conclude that in humans, heavy resistance training directed toward achieving maximum size in skeletal muscle does not result in an increase in fiber numbers.

Voluntary strength and muscle characteristics in untrained men and women and male bodybuilders

1987 ◽  
Vol 62 (5) ◽  
pp. 1786-1793 ◽  
Author(s):  
D. G. Sale ◽  
J. D. MacDougall ◽  
S. E. Alway ◽  
J. R. Sutton
Keyword(s):  
Muscle Fiber ◽  
Biceps Brachii ◽  
Peak Torque ◽  
Volume Density ◽  
Isokinetic Dynamometer ◽  
Cross Sectional ◽  
Fiber Area ◽  
Fiber Composition ◽  
Fiber Number ◽  
Voluntary Strength

Eight untrained women (F), 13 untrained men (M), and 11 male bodybuilders (BB) did maximal elbow flexions on an isokinetic dynamometer at velocities of 30, 120, 180, 240, and 300 degrees/s, from which impact torque (IT), peak torque (PT), and work (W) were measured. Biceps and total flexor cross-sectional area (CSA) were measured by computerized tomographic scanning. Muscle fiber area, fiber composition, and collagen volume density were determined from single needle biopsies of biceps brachii. Biceps fiber number was estimated as the ratio of biceps CSA (corrected for connective tissue) to mean fiber area. PT and W decreased at higher velocities in M and BB but not in F; consequently, the correlation between CSA and PT and W was lower at 300 degrees/s (r = 0.58, 0.60) than 30 degrees/s (r = 0.80, 0.79). The ratio of PT to flexor CSA was similar in all groups at 30 degrees/s, whereas F had greater ratios than M and BB at the remaining velocities. F had greater W/CSA ratios than M and BB at all velocities. IT increased at higher velocities in all groups; the increase was greater in F and M than in BB. In contrast to PT and W, the correlation between IT and CSA was greater at 300 degrees/s (r = 0.67) than 30 degrees/s (r = 0.58), and there were no differences among groups in the IT/CSA ratios. Flexor CSA correlated negatively with the ratio of IT, PT, and W to CSA. Muscle fiber composition failed to correlate with any measure of strength. M and BB had greater biceps area, fiber number, and fiber area than F.(ABSTRACT TRUNCATED AT 250 WORDS)

Fiber number, area, and composition of mouse soleus muscle following enlargement

1985 ◽  
Vol 58 (2) ◽  
pp. 619-624 ◽  
Author(s):  
B. F. Timson ◽  
B. K. Bowlin ◽  
G. A. Dudenhoeffer ◽  
J. B. George
Keyword(s):  
Muscle Fiber ◽  
Soleus Muscle ◽  
Histological Section ◽  
Type I ◽  
Muscle Weight ◽  
Cross Sectional ◽  
Male And Female ◽  
Female Mice ◽  
Fiber Area ◽  
Fiber Number

Muscle fiber number, cross-sectional area, and composition were studied in response to enlargement produced by synergistic ablation in the mouse soleus muscle. The effect of the location of a histological section on the number of fibers that appear in the section was also studied using the mouse soleus muscle. Enlargement was produced in the soleus muscle of 15 male and 15 female mice by ablation of the ipsilateral gastrocnemius muscle. Fiber counts, using the nitric acid digestion method, revealed no difference between control and enlarged muscles in male and female mice. Mean fiber area, determined by planimetry, was 49.1 and 34.5% greater following enlargement in male and female mice, respectively. Increase in muscle weight could be totally accounted for by the increase in fiber area following enlargement. A transformation of type II to type I fibers occurred following enlargement for both sexes. Counts of fibers from histological sections revealed that there was a progressive decrease in the fiber number as the section was moved from the belly to the distal end of the muscle. The results of these studies indicate that muscle enlargement in the mouse soleus muscle is due to hypertrophy of the existing muscle fibers.

Muscle hypertrophy response to resistance training in older women

1991 ◽  
Vol 70 (5) ◽  
pp. 1912-1916 ◽  
Author(s):  
S. L. Charette ◽  
L. McEvoy ◽  
G. Pyka ◽  
C. Snow-Harter ◽  
D. Guido ◽  
...  
Keyword(s):  
Resistance Training ◽  
Muscle Strength ◽  
Muscle Hypertrophy ◽  
Elderly Women ◽  
Type I ◽  
Type Ii ◽  
Cross Sectional ◽  
Resistance Training Program ◽  
Fiber Area ◽  
Muscle Groups

We conducted a 12-wk resistance training program in elderly women [mean age 69 +/- 1.0 (SE) yr] to determine whether increases in muscle strength are associated with changes in cross-sectional fiber area of the vastus lateralis muscle. Twenty-seven healthy women were randomly assigned to either a control or exercise group. The program was satisfactorily completed and adequate biopsy material obtained from 6 controls and 13 exercisers. After initial testing of baseline maximal strength, exercisers began a training regimen consisting of seven exercises that stressed primary muscle groups of the lower extremities. No active intervention was prescribed for the controls. Increases in muscle strength of the exercising subjects were significant compared with baseline values (28-115%) in all muscle groups. No significant strength changes were observed in the controls. Cross-sectional area of type II muscle fibers significantly increased in the exercisers (20.1 +/- 6.8%, P = 0.02) compared with baseline. In contrast, no significant change in type II fiber area was observed in the controls. No significant changes in type I fiber area were found in either group. We conclude that a program of resistance exercise can be safely carried out by elderly women, such a program significantly increases muscle strength, and such gains are due, at least in part, to muscle hypertrophy.

Gender- and height-related limits of muscle strength in world weightlifting champions

2000 ◽  
Vol 89 (3) ◽  
pp. 1061-1064 ◽  
Author(s):  
Lincoln E. Ford ◽  
Alvin J. Detterline ◽  
Kevin K. Ho ◽  
Wenyuan Cao
Keyword(s):  
Muscle Strength ◽  
Body Mass ◽  
Common Factor ◽  
Body Height ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Muscle Cross Sectional Area ◽  
The Relationship ◽  
Contractile Tissue

To assess factors that limit human muscle strength and growth, we examined the relationship between performance and body dimensions in the world weightlifting champions of 1993–1997. Weight lifted varied almost exactly with height squared (Ht2.16), suggesting that muscle mass scaled almost exactly with height cubed (Ht3.16) and that muscle cross-sectional area was closely correlated with body height, possibly because height and the numbers of muscle fibers in cross section are determined by a common factor during maturation. Further height limitations of muscle strength were shown by only one male champion ≥183 cm and no female champions ≥175 cm. The ratio of weight lifted to mean body cross-sectional area was approximately constant for body-weight classes ≤83 kg for men and ≤64 kg for women and decreased abruptly for higher weight classes. These findings suggest a nearly constant fraction of body mass devoted to muscle in lighter lifters and a lesser fraction in heavier lifters. Analysis also suggests that contractile tissue comprises ∼30% less body mass in female champions.

scholarly journals Postsynaptic cleft density changes with combined exercise protocols in an experimental model of muscular hypertrophy

2021 ◽  
Vol 65 (s1) ◽  
Author(s):  
Jurandyr Pimentel Neto ◽  
Lara Caetano Rocha ◽  
Carolina Dos Santos Jacob ◽  
Gabriela Klein Barbosa ◽  
Adriano Polican Ciena
Keyword(s):  
Wistar Rats ◽  
Biceps Brachii ◽  
Maximum Diameter ◽  
Type I ◽  
Muscular Hypertrophy ◽  
Type Ii ◽  
Biceps Brachii Muscle ◽  
Myofibrillar Atpase ◽  
Cross Sectional ◽  
Male Wistar Rats

The vertical ladder-based protocols contribute to the NMJ junction's adaptations, and when combined with and without load, can be potentiated. The present study aimed to investigate postsynaptic regions of the biceps brachii muscle in adult male Wistar rats submitted to different vertical ladder-based protocols (Sedentary - S; Climbing - C; Climbing with Load - LC and Combined Climbing - CC). The protocols (C, LC, CC) were performed in 24 sessions, 3 x/week, for 8 weeks. The myofibrillar ATPase analysis showed an increase in cross-sectional area (CSA) of the muscle fibers Type I in all trained Groups; Type II in C and LC and reduction in CC; Type IIx higher in all trained Groups. In the postsynaptic cleft, the stained area presents smaller in Groups C, LC, and CC; the total area showed smaller than LC and higher in C and CC. The stained and total perimeter, and dispersion showed a reduction in C, LC, and CC, higher maximum diameter in Groups C and CC, and decreased in LC. Regarding the postsynaptic cleft distribution, the stained area presented a decrease in all trained Groups. The integrated density presented higher principally in CC. The NMJ count showed an increase in all trained Groups. We concluded that the vertical ladder-based protocols combined contributed to the postsynaptic region adaptations.

Muscle fiber hypertrophy, hyperplasia, and capillary density in college men after resistance training

1996 ◽  
Vol 81 (5) ◽  
pp. 2004-2012 ◽  
Author(s):  
G. E. McCall ◽  
W. C. Byrnes ◽  
A. Dickinson ◽  
P. M. Pattany ◽  
S. J. Fleck
Keyword(s):  
Resistance Training ◽  
Muscle Fiber ◽  
Biceps Brachii ◽  
College Men ◽  
Capillary Density ◽  
Type I ◽  
Muscle Area ◽  
Cross Sectional ◽  
Fiber Number ◽  
Muscle Groups

McCall, G. E., W. C. Byrnes, A. Dickinson, P. M. Pattany, and S. J. Fleck. Muscle fiber hypertrophy, hyperplasia, and capillary density in college men after resistance training. J. Appl. Physiol. 81(5): 2004–2012, 1996.—Twelve male subjects with recreational resistance training backgrounds completed 12 wk of intensified resistance training (3 sessions/wk; 8 exercises/session; 3 sets/exercise; 10 repetitions maximum/set). All major muscle groups were trained, with four exercises emphasizing the forearm flexors. After training, strength (1-repetition maximum preacher curl) increased by 25% ( P < 0.05). Magnetic resonance imaging scans revealed an increase in the biceps brachii muscle cross-sectional area (CSA) (from 11.8 ± 2.7 to 13.3 ± 2.6 cm2; n = 8; P < 0.05). Muscle biopsies of the biceps brachii revealed increases ( P < 0.05) in fiber areas for type I (from 4,196 ± 859 to 4,617 ± 1,116 μm2; n = 11) and II fibers (from 6,378 ± 1,552 to 7,474 ± 2,017 μm2; n = 11). Fiber number estimated from the above measurements did not change after training (293.2 ± 61.5 × 103 pretraining; 297.5 ± 69.5 × 103 posttraining; n = 8). However, the magnitude of muscle fiber hypertrophy may influence this response because those subjects with less relative muscle fiber hypertrophy, but similar increases in muscle CSA, showed evidence of an increase in fiber number. Capillaries per fiber increased significantly ( P < 0.05) for both type I (from 4.9 ± 0.6 to 5.5 ± 0.7; n = 10) and II fibers (from 5.1 ± 0.8 to 6.2 ± 0.7; n = 10). No changes occurred in capillaries per fiber area or muscle area. In conclusion, resistance training resulted in hypertrophy of the total muscle CSA and fiber areas with no change in estimated fiber number, whereas capillary changes were proportional to muscle fiber growth.

Effects of resistance training on elbow flexors of highly competitive bodybuilders

1992 ◽  
Vol 72 (4) ◽  
pp. 1512-1521 ◽  
Author(s):  
S. E. Alway ◽  
W. H. Grumbt ◽  
J. Stray-Gundersen ◽  
W. J. Gonyea
Keyword(s):  
Resistance Training ◽  
Training Program ◽  
Muscle Mass ◽  
Biceps Brachii ◽  
Fiber Type ◽  
Volume Density ◽  
Elbow Flexors ◽  
Cross Sectional ◽  
Fiber Number ◽  
Muscle Cross Sectional Area

The influence of gender on muscular adaptation of the elbow flexors to 24 wk of heavy resistance training was studied in five male bodybuilders (MB) and five female bodybuilders (FB) who were highly competitive. Muscle cross-sectional area (CSA), fiber area, and fiber number were determined from the biceps brachii, and voluntary elbow flexor torque was obtained at velocities of contraction between 0 and 300 degrees/s. Biceps and flexor CSA was 75.8 and 81% greater, respectively, in MB than in FB, but muscle CSA was not significantly altered by the training program in either group. Because estimated fiber number and the volume density of nonmuscle tissue were similar in MB and FB, most of the gender difference in muscle CSA appeared to be due to greater absolute mean fiber areas in MB (10.51 and 10.68 x 10(3) microns 2 pre- and posttraining, respectively) than in FB (5.33 and 5.96 x 10(3) microns 2 pre- and posttraining, respectively). In neither MB nor FB did fiber type achieve further hypertrophy during the 24-wk training program. These data suggest that the extent of any change in muscle mass or muscle fiber characteristics is minimal after a bodybuilder of either gender has attained a high degree of muscle mass and a highly competitive status.

scholarly journals Relationship between Emotional Intelligence, Sleep Quality and Body Mass Index in Emergency Nurses

Healthcare ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 607
Author(s):  
Noelia Miguez-Torres ◽  
Alejandro Martínez-Rodríguez ◽  
María Martínez-Olcina ◽  
Laura Miralles-Amorós ◽  
Cristina Reche-García
Keyword(s):  
Body Mass Index ◽  
Emotional Intelligence ◽  
Sleep Quality ◽  
Body Mass ◽  
Working Hours ◽  
Type I ◽  
Emotional States ◽  
Emergency Nurses ◽  
Cross Sectional ◽  
Lack Of Sleep

Nurses have long working hours with high psychological burdens. In addition, in the emergency department, nurses are required to quickly adapt emotionally. The aim of this study was to describe and relate emotional intelligence (EI) skills of emergency nurses, their body mass index (BMI) and sleep quality. For this purpose, a cross-sectional was carried out in which the perceived emotional intelligence test and the Pittsburgh sleep quality index were applied. Sixty-two emergency nurses (48 women and 14 men) participated. The results indicated that the majority of them present adequate levels of EI, with no differences by gender. Younger nurses showed a better ability to feel, express and understand emotional states than the older ones, while the ability to regulate emotional states occurred in the opposite way. Nurses who have been working for several years showed a better ability to regulate emotions than those with less experience. Those who were overweight grade II and obese type I expressed their feelings better, also the regulation of emotional states decreased as weight increased. Finally, it has been observed that the quality of sleep of emergency nurses is significantly altered, and that this lack of sleep may affect their ability to process emotions.

Sign in / Sign up

Export Citation Format

Share Document