Strength, Size, and Muscle Quality in the Upper Arm following Unilateral Training in Younger and Older Males and Females

Abstract

Purpose: To assess strength, size, and muscle quality differences between younger and older males and females in response to training. Methods:The bicep and tricep of the non-dominant arm were trained for twelve weeks in younger and older males and females (n = 41). The bicep of both arms were assessed pre and post for muscle strength using one-repetition maximum (1 RM) testing, and size using magnetic resonance imaging (MRI).Results: Strength (p Ͻ 0.05), mCSA (p Ͻ 0.05), and 1 RM MQ (p Ͻ 0.00) increased in response to training in all subjects regardless of age or gender. Younger and older subjects had similar increases in strength (45.49 ± 15.30% vs. 42.67 ± 26.67% respectively), mCSA (16.22 ± 7.98% vs. 19.17 ± 6.19% respectively), and 1RM MQ (25.73 ± 15.76 vs. 19.67 ± 20.66 respectively). Women increased their strength (55.59 ± 19.45% vs. 32.87 ± 15.66% p Ͻ 0.00 respectively), size (20.36 ± 6.29% vs. 14.72 ± 7.28% p Ͻ 0.02 respectively), and 1 RM MQ (29.74 ± 18.33% vs. 16.30 ± 15.59% p Ͻ.02) more than men. In comparing age and gender, younger females increased their strength more than older males (56.42 ± 12.92% vs. 29.17 ± 21.8% p Ͻ.02 respectively). Older females also increased their strength more than older males (54.68 ± 25.73 vs. 29.17 ± 21.80% respectively). Younger females increased their 1 RM MQ more than older males (.18 ± .08 kg/cm vs. .06 ± .08 kg/cm p Ͻ.02 respectively). Conclusion:Strength and mCSA increases similarly in older and younger subjects. However, the overall strength and quality of the muscle seems to improve more in women than in men.

Resistance training induces similar adaptations of upper and lower-body muscles between sexes

“…If this holds true, then there is a logical rationale that our 2-week familiarization period was sufficient to promote considerable neural adaptations and potentially compensate initial strength gains in females. This largely explains why we did not observe such dramatic differences between elbow flexor hypertrophy and strength changes in females (24% vs. 29%) as previous studies reported 12 – 14 .…”

“…Firstly, it should be noted that we applied a research design where 1RM testing was preceded by 2 weeks of familiarization protocol. Contrary, other studies conducted one trial session before strength testing 11 – 14 . Rapid increase in strength occurs during the initial 2–4 weeks of RT and it is primarily mediated by neural adaptations 4 .…”

“…On the other hand, less attention has been paid to upper-body muscles. Based on studies 11 – 14 , it seems that females exhibit greater strength changes. Indeed, in a recent meta-analysis Roberts et al 15 concluded that RT induces similar muscular adaptations between young-adult untrained males and females for lower-body muscles.…”

Comparison of Musculoskeletal Disorder Risk based on Gender in High School Students

“…Male have larger mCSA (muscle cross sectional area) in both arms than female. And also have 1 RM (repetition maximum) greater in the dominant arm than female, but there is no difference in the non-dominant arm (Tanton et al, 2009). Snih Soham's research on lower extremity muscle strength showed that the average muscle strength for male ranges from 9.3 kg for knee extension, 12.8 kg for hip flexion, to 13.0 kg for hip abduction.…”

Genome-Wide Association Study to Identify Common Variants Associated with Brachial Circumference: A Meta-Analysis of 14 Cohorts

“…The decrease in BC that is observed in elderly men and women points to substantial subcutaneous fat loss and redistribution of fat from extremity to trunk [4] . Additionally, aging is also characterised by loss in skeletal muscle mass, known as sarcopenia [21] , [22] . To account for these effects of aging on BC we adjusted all our analyses for the age of individuals.…”