High volume vs. high intensity: which actually builds more muscle? A 2024 dose-response analysis has an answer

The "high volume vs high intensity" debate usually gets argued as if one approach must be universally superior. A 2024 series of meta-regressions modelling proximity to failure (reps in reserve, or RIR) as a continuous variable across many resistance-training studies suggests the honest answer is that it depends on whether your primary goal is strength or muscle size.

What the meta-regression found

Modelling RIR continuously against outcomes, the researchers found that training closer to failure had a negligible relationship with strength gains — meaning a wide range of proximity to failure produced similar strength outcomes. For hypertrophy, however, the relationship was meaningfully negative: as sets were taken closer to failure, muscle growth increased, with the confidence interval excluding a null effect.

How this fits with the volume data

A companion body of dose-response research on weekly set volume (including a related 2026 meta-regression from an overlapping author group) shows hypertrophy continuing to climb across a wide range of weekly sets per muscle before plateauing at a high volume, while strength responds more to load and proximity to failure being applied consistently rather than to sheer set count.

Practical application

If your primary goal is muscle size, this data supports pushing more sets closer to failure. If your primary goal is strength (with fatigue management and recoverability as real constraints), you can train with more reps in reserve without giving up strength gains, which may allow more total volume or frequency before fatigue becomes limiting.

This is exactly why Misi logs both set count and RPE/RIR per exercise rather than treating volume alone as the whole story — the two data points together are what this research shows actually predicts which outcome you’ll get.