# Effect of velocity loss squat induced post-activation performance enhancement on lower limb explosive power in sprinters

## TL;DR

This study found that a 5% velocity loss during squats at 85% of maximum weight improves sprinters' explosive power the most, with optimal results within 4-8 minutes.

## Contribution

The study identifies the optimal velocity loss threshold for inducing PAPE in sprinters using squat exercises.

## Key findings

- A 5% velocity loss condition significantly improved sprint time and jump performance within 4-8 minutes.
- The 5% condition required fewer repetitions than other thresholds to achieve performance gains.
- The 10% velocity loss also improved sprint and jump performance but with less efficiency.

## Abstract

This study aimed to identify the optimal velocity loss (VL) threshold during squats for inducing post-activation performance enhancement (PAPE) in track and field sprinters, with the goal of maximizing sprint performance.

Twenty-four sprinters performed squat-based PAPE protocols using 85% 1RM (1 Repetition Maximum) across four VL thresholds (5%, 10%, 15%, and 20%). The 30-m sprint and countermovement jump (CMJ) tests were administered at baseline and at 4, 8, 12, and 16 min post-intervention. Measurements included CMJ height, peak power, momentum, and the number of squats completed under each VL condition.

The 5% VL condition led to significant improvements in 30-m sprint time at 4 min (F(1,47) = 7.292, P = 0.01, Cohen’s d = −0.777) and 8 min (F(1,47) = 4.603, P = 0.037, Cohen’s d = −0.615), along with increases in CMJ height (F(1,47) = 5.748, P = 0.021, Cohen’s d = 0.69), peak power (F(1,47) = 5.585, P = 0.022, Cohen’s d = 0.685), and momentum (F(1,47) = 6.462, P = 0.014, Cohen’s d = 0.715). Under the 10% VL condition, significant gains were observed in 4-min sprint performance (F(1,47) = 5.288, P = 0.026, Cohen’s d = −0.656) and CMJ peak power at 4 min (F(1,47) = 5.585, P = 0.014, Cohen’s d = 0.741) and 8 min (F(1,47) = 3.884, P = 0.022, Cohen’s d = 0.687). The number of squats performed was significantly lower at 5% VL compared to other thresholds (P < 0.001).

A velocity loss threshold of 5% during squats at 85% 1RM elicits a significant PAPE effect by 4 min post-exercise, with the fewest required repetitions. For practical application, a recovery interval of 4–8 min is recommended to optimize training outcomes in sprinters.