Table 1. Body composition and gastrocnemius medialis (GM) muscle strength (n=142), size and architecture (n=127) of the study participants according to age and body fat percentage (BF%).
| Variable | Young (n=75) | Older (n=67) | ||
|---|---|---|---|---|
| Normal BF% (n=52) | High BF% (n=23) | Normal BF% (n=23) | High BF% (n=44) | |
| Age (yrs) | 24.04±8.42 | 28.04±9.69 | 65.52±7.98a | 66.02±7.29a |
| Height (m) | 1.70±0.10 | 1.68±0.08 | 1.63±0.09a | 1.65±0.06a |
| Body mass (kg) | 65.56±13.50 | 94.93±14.13b,c | 62.23±14.13a | 79.65±14.64a,b |
| BMI (m/kg2) | 22.75±3.87 | 33.81±4.86b,c | 23.16±3.43a | 29.23±5.33a,b |
| Body fat (%) | 27.59±6.92c | 43.30±6.56b | 32.31±9.93 | 40.60±7.04b |
| Body fat mass (kg) | 17.70±6.42 | 40.13±8.85b,c | 19.59±5.72a | 31.64±9.70a,b |
| Body lean mass (kg) | 43.62±9.53 | 49.60±8.26b | 38.89±9.67a | 43.26±8.14a,b |
| iMVC PF torque (N·m) | 173.64±44.17 | 200.75±42.92b | 133.37±36.60a | 145.20±34.41a,b |
| ikMVC PF torque (N·m) | 92.34±25.18 | 102.00±21.10 | 60.51±20.83a | 63.27±20.85a |
| VA (%) | 95.29±5.51 | 88.02±11.04b | 86.58±14.15a | 84.28±12.05a,b |
| Ft (N) | 5245±1357 | 5949±1631b | 4026±1079a | 4400±1055a,b |
| GM Ff (N) | 1221±334 | 1471±427b | 930±274a | 1042±273a,b |
| GM Vm (cm3) | 214.59±61.61 | 310.75±59.37b,c | 203.66±43.24a | 217.11±49.19a,b |
| GM θp (°) | 30.58±5.09 | 35.10±3.95b | 27.71±4.73a | 30.36±4.60a,b |
| GM Lf (cm) | 3.65±0.58 | 3.73±0.54 | 3.94±0.78 | 3.86±0.60 |
| GM PCSA (cm2) | 60.20±16.52 | 85.86±18.00b,c | 52.50±13.23a | 57.14±13.93a,b |
| iMVC/BM (N·m/kg) | 2.59±0.58 | 1.99±0.36b | 2.10±0.41a | 1.71±0.34a,b |
| ikMVC/BM (N·m/kg) | 1.43±0.28 | 1.09±0.25b | 0.97±0.25a | 0.80±0.25a,b |
| iMVC/Vm (N·m/cm3) | 0.81±0.18c | 0.65±0.14b | 0.66±0.14 | 0.68±0.15b |
| ikMVC/Vm (N·m/cm3) | 0.43±0.12c | 0.34±0.09b | 0.30±0.10a | 0.30±0.08a,b |
| GM specific force (N/cm2) | 21.07±5.85 | 17.59±5.28 | 18.35±5.33 | 18.80±4.72 |
Abbreviations: BM, body mass; BMI, body mass index; Ft, maximum Achilles tendon force; GM Ff, gastrocnemius medialis fascicle force; ikMVC, isokinetic maximum voluntary contraction; iMVC, isometric maximum voluntary contraction; Lf, muscle fascicle length; PCSA, physiological cross-sectional area; VA, voluntary muscle activation; Vm, muscle volume; θp, muscle fascicle pennation angle.
Values are mean±s.d.
a
Significant effect of age (P<0.05).
b
Significant effect of BF% (P<0.05).
c
Significant age × BF% interaction (P<0.05).