Low load or high load resistance training?
Low load: ≤60% 1 Repetition maximum (RM)
High load: ≥65% 1 RM
A meta- analysis by Schoenfeld et al, 2016 have suggested that both high and low loading strategies are able to stimulate muscle hypertrophy and increase muscle strength in untrained individuals. On average, the participants in the various papers that were reviewed had resistance training of 3 times a week for 8 weeks. A trend was noted that high load resistance training was more superior than low load resistance training in improving muscle hypertrophy and strength.
Those who work closely with elderly people should take into consideration the findings of this meta-analysis.
Bottom line: Both low and high loads would improve muscle mass and strength.
Reference: Schoenfeld, Jacob M. Wilson, Ryan P. Lowery & James W. Krieger (2016) Muscular adaptations in low- versus high-load resistance training: A meta-analysis, European Journal of Sport Science, 16:1, 1-10.