Effect of velocity-based training on performance

In gyms and in high-level sports, load prescription is still largely based on a traditional approach: a percentage of 1RM, i.e., the maximum load an athlete can lift once. This method has long been considered the gold standard for calibrating training intensities. However, it has a fundamental weakness: it does not take into account daily fluctuations in performance.

Between fatigue, stress, sleep, nutrition, and biological rhythms, an athlete’s strength can vary by up to 36% from one day to the next. Training at 80% of 1RM does not have the same effect if, on that particular day, the athlete is at peak fitness or lacking in recovery. This is where Velocity-Based Training (VBT) comes in. This self-regulating method adjusts loads in real time based on the speed of each repetition.

The idea is simple: the speed of the barbell is a direct reflection of the relative load. The slower the bar moves, the heavier the load (as a percentage of 1RM). By tracking this data using a sensor or app, the coach can adjust the workload, number of repetitions, and total volume according to the athlete’s form on that day. VBT therefore allows for more individualized, more precise, and potentially more effective training, especially for experienced athletes. But what about performances?

The study

To answer this question, a team of Chinese researchers conducted a meta-analysis to examine the impact of VBT on four key components of lower body performance: maximum strength, strength endurance, vertical jump, and sprint speed. The criteria for selecting studies included that participants had at least one year of strength training experience, did not engage in other training during the intervention period, and the protocols included pre- and post-intervention measurements of the following four performance indicators:

A total of nine studies were selected, published between 2017 and 2021, representing 253 men aged 22 to 26, all of whom were trained athletes. Eight of these studies used the T-Force Dynamic system (Spain) to measure barbell speed, and one used the GymAware Power Tool (Australia). All used the squat as the main exercise, at a rate of 2-3 sessions per week, for 6 to 8 weeks.

Intensities ranged from 50 to 85% of 1RM, and the “velocity loss” (VL) per set was between 5 and 45%. This parameter indicates the decrease in speed tolerated before stopping a set: for example, a VL of 20% means that the athlete stops as soon as the barbell speed drops by 20% compared to their first repetition. This variable is essential because it determines the level of neuromuscular fatigue induced.

The researchers assessed the quality of the studies using the PEDro grid: eight were judged to be of good quality and one of average quality. Statistical analyses were then performed using a random effects model, using the standardized mean difference (SMD) to compare the effects between studies.

Results & analyses

The main results of this analysis showed that VBT significantly improves all components of performance tested, with virtually no heterogeneity between studies.

1. Maximum strength

VBT induces a significant increase in 1RM with a medium effect size (SMD=0.76, p<0.001). In other words, athletes who train for speed gain significant strength, despite often lower training volumes than traditional protocols. This effectiveness is particularly interesting for experienced athletes, for whom the margins for improvement are small. The fact that all studies report significant gains underscores the robustness of this method.

2. Strength endurance

The effect is even more pronounced on strength endurance, with a large effect size (SMD=1.19, p<0.001). The authors explain this result by selective hypertrophy of slow fibers or heavy myosin type I chains, stimulated by greater velocity losses. In other words, when VBT is programmed with a higher fatigue tolerance (e.g., VL≥30%), it promotes muscle adaptations associated with strength endurance. This result is consistent with the work of other researchers (Pareja-Blanco et al., 2017) who showed, via muscle biopsies, that training with controlled velocity loss modulated the proportion of muscle fibers according to the chosen strategy: a low VL led to the maintenance of fast fibers and muscle power; a high VL led to an adaptation towards slow fibers and better strength endurance.

3. Vertical jump (power)

The vertical jump also improved, with a medium effect size (SMD=0.53, p<0.001). VBT therefore appears to be as effective as traditional methods for developing muscle power, while inducing less cumulative fatigue. This can be explained by better quality of execution: by stopping the sets before technical deterioration, athletes preserve their explosiveness and promote more specific nervous adaptation.

4. Sprint

The sprint time over 10 to 20 meters decreases significantly (SMD=–0.40, p<0.001). However, it is interesting to note that, although the overall result is positive, nearly half of the included studies reported no or even negative effects on sprint results. The authors note that the studies with no results had adapted a relatively greater velocity loss (>20%). As mentioned above, velocity loss is closely related to selective muscle hypertrophy. Excessive velocity loss could reduce the percentage of heavy myosin IIX chains and thus inhibit associated explosive athletic performance, such as sprinting.

Practical applications

The results of this meta-analysis confirm that VBT improves strength, power, endurance, and speed, while optimizing workload and reducing fatigue (by managing velocity loss). From a practical standpoint, VBT offers a modern training framework focused on individual regulation and stimulus quality. For experienced athletes, it is a more refined and responsive alternative to traditional methods based on 1RM.

Thus, VBT allows for performance gains comparable to, or even superior to, traditional training, while reducing the total volume of work and accumulated fatigue. Daily adjustment of loads according to actual bar velocity improves the accuracy of the mechanical load applied. Whereas training based on a fixed percentage of 1RM does not take into account daily biological variations, VBT allows you to always train at the right intensity, neither too much nor too little.

It improves the quality of execution, a point that is often underestimated. By stopping a set as soon as the velocity falls below a defined threshold, unnecessary repetitions and technical deterioration are avoided. This promotes long-term performance and reduces the risk of injury, especially on heavy exercises such as squats or bench presses.

Finally, VBT introduces an additional motivation lever. By providing instant and objective feedback (via bar velocity), it transforms training into a measurable performance game. This immediate feedback stimulates concentration, commitment, and progress.

Reference

Zhang, X., Feng, S., Peng, R., & Li, H. (2022). The Role of Velocity-Based Training (VBT) in Enhancing Athletic Performance in Trained Individuals: A Meta-Analysis of Controlled Trials. International Journal of Environmental Research and Public Health, 19(15), 9252.