Mixed
Low-load resistance exercise performed to volitional failure stimulates myofibrillar protein synthesis for a longer duration (sustained at 24 hours) compared to high-load resistance exercise, despite similar acute (4-hour) stimulation.
If you cannot lift heavy weights due to joint issues or equipment limitations, you can still stimulate muscle growth by using lighter weights (e.g., 30% of your max) and performing enough reps to reach failure. While heavy weights might spike muscle building signals faster in the first few hours, light weights keep those signals active much longer (up to 24 hours), potentially making them equally or more effective for long-term muscle gain.
These results suggest that low-load high volume resistance exercise is more effective in inducing acute muscle anabolism than high-load low volume or work matched resistance exercise modes.
Why this rating
Randomized controlled trial with rigorous metabolic tracing and biopsy methods, though limited to young, healthy men.
Source
Low-Load High Volume Resistance Exercise Stimulates Muscle Protein Synthesis More Than High-Load Low Volume Resistance Exercise in Young Men
Nicholas A. Burd et al. · PLoS ONE · 2010
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