Intake of lean red meat confers no additional benefits in adults on exercise training

Consumption of lean red meat in line with current recommendations does not improve muscle mass, strength, or cognitive functions of healthy community-dwelling older adults undertaking resistance-based exercise training 3 days/week compared to those consuming carbohydrates, a study has shown.

The investigators randomized 154 adults aged ≥65 years who participated in a multicomponent 3-day/week resistance-based exercise programme to either a lean red meat group (two 80-g servings of cooked red meat), the exercise plus lean red meat (Ex + Meat) group (n=77), or a control group receiving carbohydrates in the form of one-half cup (approximately 225 g cooked weight) or rice or pasta or 1 medium potato, the exercise plus carbohydrate control (C + Ex) group (n=77), on training days.

No significant between-group difference in exercise-induced improvements was observed for the following primary outcomes: total body lean mass (LM; 0.6 to 0.8 kg), leg LM (0.1 to 0.2 kg), thigh muscle cross-sectional area (3.7 percent to 4.9 percent), leg and back muscle strength (26 percent to 40 percent), and executive function (z-score standard deviation [SD], 0.33 to 0.39).

Improvements also did not differ significantly for the secondary outcomes of global cognition function (0.17 to 0.23 SD), fat mass (–0.65 to –0.75 kg), physical function measures (sit-to-stand, both 15 percent; 4-square step test, 2 percent to 7 percent), or systolic blood pressure (–3.2 to –4.1 mm Hg).

Notably, improvements were greater for the Ex + meat group than the C + Ex group in terms of arm LM (0.07 kg, 95 percent confidence interval [CI], 0.01–0.14; p=0.029), gait speed (0.05 m/s, 95 percent CI, 0.00–0.11; p=0.042), muscle density (1.0 percent, 95 percent CI, 0.2–1.9; p=0.015), and appendicular LM in the per-protocol analysis (0.21 kg, 95 percent CI, 0.02–0.40; p=0.03).

On the other hand, net improvements in working memory learning after 12 weeks (SD, 0.24, 95 percent CI, 0.05–0.43; p=0.011) and 24 weeks (SD, 0.27, 95 percent CI, 0.06–0.49; p=0.007) were greater in the C + Ex group than the Ex + Meat group.

Inflammatory and neurotrophic markers were unchanged in either group.