Can different training protocols be reliably distinguished by muscle growth measurements?
What the Evidence Shows
We analyzed the available evidence on whether different training protocols can be reliably distinguished by muscle growth measurements, and what we’ve found so far is mixed. Fifty-four studies suggest that the changes in muscle size from different workout routines may be too small to measure accurately with current tools, making it hard to tell which routine is truly more effective. At the same time, fifty-nine studies refute this idea, implying that differences in muscle growth between routines might be detectable under certain conditions.
This means the tools we currently use to track muscle growth — like DEXA scans, ultrasound, or bioimpedance — may not be precise enough to consistently pick up small differences between training styles. Even if one program leads to slightly more growth, the measurement error could be as large as the actual effect, making it impossible to say for sure which is better. Some studies show clear differences, but others find no meaningful separation between protocols, even when people follow them for months.
We don’t know if the problem lies in the measurement tools, the way studies are designed, or whether the real differences between routines are simply too small to matter in most cases. The evidence we’ve reviewed leans toward uncertainty — not because one method is clearly superior, but because we can’t yet measure the outcomes reliably enough to tell them apart.
In everyday terms: if you’re trying to choose between two workout plans based on which one builds more muscle, the data doesn’t give you a clear answer. The differences might be real, but we can’t measure them well enough yet to be confident.
Evidence from Studies
Differences in muscle hypertrophy between training protocols may fall within the range of typical measurement error and thus cannot be reliably distinguished.
Similar muscle hypertrophy following eight weeks of resistance training to momentary muscular failure or with repetitions-in-reserve in resistance-trained individuals
DOI: 10.1080/02640414.2024.2321021
The effect of myofibril and sarcoplasmic hypertrophy training on muscle hypertrophy and strength
DOI: 10.1007/s11332-025-01565-w
Unilateral low-load blood flow restriction vs. high-load training in the Bulgarian split squat: a randomized within-subject design on strength, hypertrophy, and asymmetry
DOI: 10.3389/fphys.2026.1786733
Mixing Up Muscle Lengths: The Effects of Training at Different Muscle Lengths in the Elbow Flexors
DOI: 10.51224/SRXIV.486
Update History
- May 26, 2026New topic created from assertion