Training for strength vs hypertrophy. That’s what Dr Brad Schoenfeld and his team sought to compare in their new study which was published today ahead of print in the Journal of Sports Science and Medicine.
What the researchers did
Subjects and training
The researchers recruited 19 (26 initially, but 7 dropped out) young males with consistent resistance training experience of at least one year and assigned them to one of two groups:
- The low rep, high load group (3 sets of 2-4 reps)
- The moderate rep, moderate load group (3 sets of 8-12 reps)
Seven exercises were performed (4 for the upper body and 3 for the lower body) to the point of concentric muscular failure on 3 non-consecutive days per week for 8 weeks.
The subjects were instructed to maintain their usual dietary habits, while adherence was assessed twice during the study by having the subjects complete 5-day food records using MyFitnessPal.com, which were collected one week before the start and during the final week of the study.
Muscle thickness was measured using ultrasound imaging 48-72 hours before the start and after the completion of the study, while muscle strength was assessed by 1RM testing for the back squat and bench press at least 48 hours before the start and after the completion of the study.
For this strength vs hypertrophy study, the statistical analysis showed:
- overall greater strength gains in the low rep, high load group
- overall greater hypertrophy gains for the moderate load, moderate rep group, especially for the quadriceps
Regarding the strength differences between groups, the researchers state that:
it can be speculated that neural adaptations associated with training close to one’s 1RM were responsible for the superior strength increases when using heavy loads.
This is in line with the principle of specificity, which states that adaptations within the muscle are dependent upon the specific program employed, as well as with previous research by Mangine et al, which also showed superior strength increases with loads of 3-5RM vs 8-12RM.
With regards to the differences in muscle hypertrophy, it is inferred that:
Given that weekly volume for MODERATE was more than double that for HEAVY, this could seemingly explain the superior gains in muscle growth seen with moderate load training in the present study.
This makes perfect sense, since previous work from Dr Schoenfeld’s lab, which compared strength vs hypertrophy training with equated training volumes, found no differences between groups for muscle hypertrophy, giving support to the hypothesis that training volume (provided that it is performed with at least moderately heavy loads) is the primary cause of muscle hypertrophy.
Training for strength vs hypertrophy: conclusions
The findings of this new strength vs hypertrophy study confirm that muscular adaptations to resistance training are dependent upon the specific program employed and that:
- programs using high loads result in higher 1RM strength gains, while
- programs using moderate loads provide a more time-efficient way of accumulating higher training volumes and, thus, maximize muscle hypertrophy more efficiently.
With the above in mind, those who are primarily concerned with maximizing 1RM strength gains should spend the majority of their training using heavier loads, while those who are primarily concerned with maximizing hypertrophic gains should spend more time training with moderate loads, since these provide a more time-efficient way of accumulating training volume and, therefore, build muscle.
It’s also worth noting that combining higher and lower loading within the context of a properly periodized resistance training routine, may have synergistic effects on strength and hypertrophy.
More great information about what causes muscle growth can be found in our recent interview with Eric Helms on training for muscle and strength.