Building muscle doesn't require hefty weights – here's a science-supported guideline to adhere to if you're working with lighter weights instead
In a surprising twist to traditional weightlifting, a certified trainer and Technogym ambassador, James Stirling, has shared a lesson on his Instagram account that suggests lifting light weights close to failure can promote muscle growth equivalently to heavy weights. This approach, supported by a 2015 study published in The Journal of Strength and Conditioning Research, challenges the long-held belief that only heavy lifting builds muscle.
The workout involves performing three sets of each exercise, working close to failure on each. According to Stirling, taking each set close to failure ensures enough load to build muscle, regardless of rep range. The key to this method lies in the principles of mechanical tension, metabolic stress, and muscle fatigue, all of which contribute to muscle hypertrophy, provided the effort is sufficient.
Muscle growth, or hypertrophy, is stimulated when the stress on muscle fibers exceeds their usual workload. This stress can be achieved either through heavy weights or lighter weights lifted to near muscular failure, where fatigue forces maximal motor unit recruitment. A critical factor is training to or near fatigue, ensuring that even with lighter weights, the muscle fibers are fully activated, producing enough tension over time to stimulate growth.
Exercise scientist Brad Schoenfeld's research confirms that short, intense workouts with high effort can produce similar hypertrophy to longer sessions with heavier weights. The mechanism involves energy depletion in muscle cells, activating signaling pathways that promote muscle repair and growth after training, as long as the effort threshold is met.
Progressive overload remains essential, whether with heavy or light weights, meaning weights or reps should be increased over time to continually challenge muscles. Stirling suggests increasing weights when it feels comfortable to follow the principle of progressive overload.
Stirling's full-body workout consists of seven exercises, four of which are combined into two supersets. For the supersets, perform one set of exercise A, then move straight onto exercise B. After finishing the set of exercise B, rest for one minute, then return to exercise A and continue that pattern until completing three sets of each exercise.
Aim for small progressions in reps or the weights lifted. The weight starts slowing down when lifting it, and you might feel like your muscles are on fire. These are Stirling's two telltale signs for knowing when close to muscle failure.
Research suggests that muscle growth can be achieved with light or heavy weights, as long as the set is taken to near failure (1-2 reps left). A more recent preprint by Schoenfeld's team found that just two 30-minute sessions of resistance training a week is sufficient to build size and strength. Alternatively, add more volume each week by increasing the number of sets completed.
This approach is particularly valuable for those who may not be able to lift heavy weights due to injuries or other constraints, enabling effective hypertrophy with lower loads. However, total training volume and recovery should still be managed appropriately for optimal results.
In summary, lifting light weights near failure can promote muscle growth equivalently to heavy weights, provided the muscles are taken close to the limit of their capacity in each set, ensuring maximal recruitment and metabolic stress. This challenges the traditional view that only heavy lifting builds muscle and highlights the importance of training intensity and effort over load alone.
- James Stirling's shared Instagram lesson proposes that light weights lifted close to failure can promote muscle growth equally effectively as heavy weights.
- The workout suggested by Stirling involves performing three sets of each exercise, ensuring each set is taken close to failure to build muscle, regardless of rep range.
- Exercise scientists like Brad Schoenfeld confirm that short, intense workouts with high effort can produce similar muscle growth as longer sessions with heavier weights.
- To continually challenge muscles and stimulate muscle growth, progressive overload is essential, whether through heavy or light weights, suggesting an increase in weights or reps over time.
- This light-weight approach to building muscle growth, which is supported by research, is particularly valuable for individuals who may be unable to lift heavy weights due to injuries or other constraints.
