Author(s): JANSSEN, T., LOWISZ, C., LEES, M., MCKENDRY, J., LIM, C., LYONS, S., OSMAVANDANY, A., NANTHAKUMAR, A., PHILLIPS, S., Institution: MCMASTER UNIVERSITY, Country: CANADA, Abstract-ID: 230

INTRODUCTION:
Traditional strength training emphasizes higher loads (>80% 1RM); however, lower-load protocols (30-50% 1RM) effectively support strength gains and functional benefits and may be more acceptable in older persons. Consumption of higher-quality protein can enhance training adaptations and help mitigate sarcopenia. Some reports have shown that collagen peptides have greatly enhanced training adaptations in older persons. We compared whey protein (high in EAAs and leucine) to collagen protein (low in EAAs and leucine) in supporting gains in lean mass in older males and females. We hypothesized that a 12-week lower-load strength training protocol with protein supplementation would increase lean mass and improve strength and physical function, but to a greater extent in whey versus collagen protein supplementation in older adults.
METHODS:
In this randomized, double-blind, parallel group study, participants underwent DXA scans and assessments of 5RM, isometric strength, and physical function before and after 12 weeks of strength training. Participants were randomized to receive either whey (n=35, 19 female/16 male) or collagen protein (n=32, 22 female/10 male), 25g twice daily. Training consisted of 3 x 1h supervised training sessions/wk, alternating between lower-body (leg press, leg extension, and leg curl) and upper-body (lateral pulldown, chest press, and horizontal row) sessions. For each exercise, participants performed 3 sets of 20-25 repetitions at ~30-50% of their 1RM, with the final set taken to momentary muscular fatigue.
RESULTS:
Linear mixed model analysis showed a significant interaction for lean mass (p<0.001). Post-hoc analyses revealed that collagen supplementation led to a modest increase in lean mass (+0.41 kg, p=0.013, d = 0.45), whereas whey protein supplementation resulted in greater increases in lean mass (+1.24 kg, p<0.001, d = 1.39), with no sex-based differences (p>0.05). 5RM strength, isometric MVC, grip strength, and physical function improved in both groups (all with a main effect of time, p<0.05), with no sex-based differences (p>0.05).
CONCLUSION:
A 12-week progressive lower-load strength training protocol combined with whey protein supplementation increased lean mass to a greater extent than collagen protein supplementation. However, both groups improved grip strength, 5RM, isometric MVC strength, and physical function, with no between-group differences, suggesting that lower-load resistance training is effective in improving strength and function regardless of protein supplementation. These findings indicate that whey protein supplementation is more effective at increasing lean mass, while resistance training drives comparable functional benefits regardless of protein source.