Increased Leg Strength After Concurrent Aerobic and Resistance Exercise Training in Older Adults Is Augmented by a Whole Food-Based High Protein Diet Intervention

Abstract

Most studies in older adults have utilized powdered protein supplements or oral nutrition solutions as a source of additional dietary protein, but whole foods may provide a greater anabolic stimulus than protein isolated from food matrices. Therefore, the present study investigated a concurrent aerobic and resistance exercise training program in older adults, in the absence or presence of a high protein whole food-based dietary intervention, for effects on strength, physical function, and body composition. Community-dwelling older adults (n = 56; M/F, 28/28; age, 69.3 ± 4.0 years; BMI, 26.6 ± 3.7 kg m−2) participated in a 12-week intervention after randomization to either nutrition only (NUTR; n = 16), exercise only (EX, n = 19), or nutrition plus exercise (NUTR + EX, n = 21) groups. NUTR and NUTR + EX followed a dietary intervention targeting an increase in protein-rich meals at breakfast, lunch, and dinner. Exercise training in EX and NUTR + EX consisted of 24 min sessions of concurrent aerobic and resistance exercise performed three times per week. Daily protein intake increased in NUTR and NUTR + EX, but not EX. The increase in 1RM leg press strength was greater (Interaction effect, P = 0.012) in NUTR + EX [29.6 (18.1, 41.0) kg] than increases observed in NUTR [11.1 (−1.3, 23.6) kg] and EX [12.3 (0.9, 23.8) kg]. The increase in 1RM chest press strength was greater (interaction effect, P = 0.031) in NUTR + EX [6.3 (4.0, 8.6) kg] than the increase observed in NUTR [2.9 (0.3, 5.5) kg], but not EX [6.3 (3.9, 8.7) kg]. Hand-grip strength and sit-to-stand performance were each improved in all three groups, with no differences observed between groups (interaction effect, P = 0.382 and P = 0.671, respectively). An increase in percentage body fat was observed in NUTR, but not in EX or NUTR + EX (interaction effect, P = 0.018). No between-group differences were observed for change in lean body mass (interaction effect, P = 0.402). Concurrent aerobic and resistance exercise training improves strength and physical function in older adults, but combining this training with an increase in daily protein intake through whole foods may be advantageous to increase lower limb strength.

Association of Protein Intake with Handgrip Strength and Its Relation to Strength Exercise in Korean Adults Aged over 60 Years in the KNHANES (2014-18)

“…Meta-analyses analyzing RCTs conducted with elderly subjects also have shown that protein supplementation alone is ineffective and that protein supplementation combined with resistance training is more effective in enhancing muscle mass and strength [ 10 , 22 , 31 , 32 ]. In the combined exercise and high protein whole food-based diet intervention, dietary intervention enhanced the training-induced improvements in lower limb strength of older adults, compared to an exercise or diet only intervention [ 33 ], which also supports the findings of this study.…”

Nutritional supplementation to enhance the efficacy of exercise training in older adults: what is the evidence from the latest randomized controlled trials?

“…Of interest, a ‘whole-food protein approach’ was used to increase protein intake in the protein+exercise and the protein-only group from ∼1.0 to ∼1.5 g/kg body mass per day. The combined protein+exercise intervention resulted in a statistically larger improvement in lower extremity strength when compared with the exercise-only group, as well as a larger improvement in appendicular lean mass, although the latter finding did not reach statistical significance [16 ▪▪ ]. As noted by the authors, the benefits may be explained by the large increase in protein intake reached through their whole-food approach, adding an extra 40–55 g protein on a daily basis.…”

“…Finally, a recent study that did show an added benefit of protein supplementation on top of a moderate-intensity to high-intensity exercise program was performed by Timmons et al [16 ▪▪ ]. In their study, 56 healthy older men and women performed 12 weeks of supervised, high-intensity concurrent exercise known to improve muscle strength, physical function, and body composition.…”

Efectos de una Intervención Nutricional Asociada a Entrenamiento Concurrente en la Composición Corporal de Hombres Físicamente Activos

“…Nuestros resultados están acordes con estudios previos donde la intervención nutricional se establece como un componente importante cuando la actividad física o el ejercicio forman parte de la intervención para generar cambios en la composición corporal. Esta función permite aumentar los beneficios de los resultados del programa de formación en diferentes factores (Timmons et al, 2021). Sin embargo, no toda la evidencia respalda la importancia de asesorar sobre nutrición en combinación con un programa de entrenamiento cuando se midieron los beneficios relacionados con la salud, los cambios en la composición corporal y las adaptaciones al entrenamiento en mujeres sanas (Kyröläinen et al, 2018).…”