Training Volume Alone Doesn't Drive Fatigue, New Bench Press Study Finds
Researchers used velocity-based rest periods to isolate volume from fatigue, and found no added cardiovascular or metabolic cost at higher rep counts.
This study looked at whether training volume on its own drives the fatigue, cardiovascular strain, and recovery demands of a bench press session, or whether fatigue accumulation is the real factor at play. Researchers had trained men complete three bench press protocols of different volumes using individualised inter-repetition rest, a method designed to limit velocity loss within the set. The aim was to separate the effect of volume from the effect of fatigue, something previous studies hadn't been able to do well.
Aims and Methods
The researchers wanted to examine the acute mechanical, metabolic, and cardiovascular responses to different bench press volumes, and how long it took for strength to recover afterwards. Fourteen moderately trained men performed three protocols a week apart, in randomised order, each using a single set at the same relative intensity (70% of one-rep max) but differing in total reps:
LOW: 3 repetitions
MOD: 15 repetitions
HIG: 24 repetitions
To prevent fatigue from building up disproportionately in the higher-volume sets, the researchers used velocity-based training with individualised inter-repetition rest. A linear velocity transducer tracked mean propulsive velocity (MPV) on every rep. If the drop-off between the fastest rep and the following ones stayed small, rest was kept short, around 10 seconds. As velocity loss increased, rest periods were extended in increments, growing to 20 seconds, then 30 seconds, and so on, scaling directly with how much speed was lost on a given rep. This meant rest periods were not fixed in advance. They adjusted in real time based on how each individual was performing, with the goal of keeping velocity loss low and consistent across all three protocols regardless of total reps completed.
Before and after each session, the team measured heart rate, blood pressure, oxygen saturation, and blood lactate. Strength was retested immediately after exercise, then again at 24 and 48 hours, using three reps at 60% of one-rep max, to track how performance recovered over time.
Results
Performance within each session (best, average, and final MPV, along with velocity loss) did not differ between protocols. Heart rate increased during exercise but showed no difference between low, moderate, and high volume. Blood pressure showed a similar pattern across protocols. Oxygen saturation stayed stable in all three. Blood lactate rose after exercise in every protocol, but the increase was comparable regardless of volume.
Strength recovery followed the same trend. The high-volume protocol showed a small drop in performance immediately after exercise, but by 24 and 48 hours, all three protocols had recovered to a similar or improved level compared to baseline, with no meaningful differences between groups.
Practical Takeaways
When fatigue was controlled for using individualised inter-repetition rest, training volume alone did not increase cardiovascular or metabolic strain, and it did not slow recovery. This supports the idea that velocity loss, not rep count, is the primary driver of acute fatigue and recovery demands in resistance training.
For coaches and athletes, this suggests that inter-repetition rest can be used to accumulate higher training volume without the cardiovascular or metabolic cost typically associated with high-rep sets. This may be useful for athletes managing blood pressure sensitivity or needing to control fatigue during periods of high training load. The study was limited to the bench press, used a small sample of moderately trained men, and did not include female participants, so these findings should not yet be generalised to other exercises or populations.
Reference
Páez-Maldonado JA, Lluch ÁC, Ortega-Becerra M, Pareja-Blanco F. Effects of Bench Press Volume on Performance, Recovery, and Physiological Response. Sports. 2026; 14(2):76. https://doi.org/10.3390/sports14020076