Evidence-Based Physical Activity Recommendations: Part 2
This article is the second in a series of the physical activity recommendations, with an emphasis on muscular hypertrophy and strength.
Are you interested in gaining muscle mass or muscular strength but do not know where to start? In my previous article, the current physical activity guidelines for adults are summarized. This article will describe evidence-based recommendations for resistance training according to the National Strength and Conditioning Association and American College of Sports Medicine, specifically summarized from the American College of Sports Medicine’s position statement “Progression Models in Resistance Training for Health Adults.” There may be individual differences in response to resistance training, and the following information should be used as a starting point for those who seek to improve muscular hypertrophy and muscular strength.
Although, there are general muscle-strengthening guidelines for adults, those recommendations were designed as a starting point for untrained, healthy adults. Key professionals from the National Strength and Conditioning Association and American College of Sports medicine published evidence-based guidelines for healthy adults who seek to improve their muscular fitness. Two of the muscular fitness components summarized in the article include muscular hypertrophy and muscular strength. Muscular hypertrophy is an increase in muscle size. Muscular hypertrophy is an adaptation to muscle-strengthening exercise and is usually observed in the short (6 or more weeks) and long term. Recommendations for muscular hypertrophy include performing multi-joint exercises for 2 or more sets using a weight you can complete only 8 to 12 repetitions. The recommendation for individuals with longer resistance training experience (6 or more months of consistent resistant training) is 3 to 6 sets per exercise using a weight one can only complete 6 to 12 repetitions. However, muscular hypertrophy adaptations can also be observed using a number of set/repetition schemes, with new evidence suggesting that higher repetitions may also produce increases in muscular hypertrophy among trained individuals (Strength and hypertrophy adaptations between low- versus high-load resistance training: A systematic review and meta-analysis). Individuals with a shorter resistance training experience seeking to increase muscular hypertrophy should train the entire body over 2 to 3 days per week. More advanced individuals should increase the training frequency from 4 to 6 days per week, with each body part being trained 1 to 2 days per week.
In regards to muscular strength, the recommendations are similar to muscular hypertrophy. The strength training recommendation is to select a weight you can perform for 6 repetitions or less, although muscular strength increases can still be observed from 8 to 12 repetitions for an exercise. Additionally, the recommendation is to increase the rest time between sets (2 to 5 minutes vs. 30 seconds to 1.5 minutes).
In summary, there are evidence-based recommendations for those who prefer to pursue muscular hypertrophy and muscular strength goals from resistance training. Although, the recommendations are similar, training for muscular strength goals typically involves lower repetitions and a greater rest period between sets. For further information about resistance training, please visit the National Strength and Conditioning Association and American College of Sports Medicine.