Authors: Chaouachi A, Poulos N, Behm D, et al.,

Applied Physiology, Nutrition & Metabolism. October 2011;36(5):736-747

Commentary by Matt Jordan

Background

Post-activation potentiation (PAP) is the enhancement in muscle force production that occurs following a conditioning activity involving submaximal or maximal muscular contractions. For example, a coach may prescribe a set of heavy back squats done at 90% of an athlete’s maximum followed by explosive jumps with the intent of eliciting greater force production in the jumps than would have been seen otherwise. While PAP has been well documented in controlled laboratory settings, supporting scientific evidence in real-world situations such as the weight room or field of play is more tenuous. Many experts argue that the underlying reason for this lack of evidence is due to the sensitivity of PAP to the loading parameters of the conditioning activity such as its timing, intensity and volume.

Purpose of the Study

The purpose of this study was to assess the effectiveness of conditioning activities performed with a variety of intensities and volumes on functional muscular performance over a 15-minute time period.

Study Design

Twelve elite male volleyball players participated in the study. Following a standardized warm up the subjects performed maximal jumps to establish a baseline. A conditioning activity of half squats was then performed and done with volumes and intensities ranging from 10 repetitions at 70% of maximum to 1 repetition at 90% of maximum. Each conditioning activity was administered in a randomized order and done on separate days. Following the conditioning activity the subjects performed maximal jumps at various intervals over a 15-minute period to see whether or jumping was potentiated.

Main Findings

1. There was great inter-individual variability in the potentiation of jump power and velocity leading the authors to state the importance of individualizing potentiation protocols.

2. With weak statistical support it appeared that the moderate loads and volumes (5 reps @ 70%; 3 reps @ 85%) were most likely to potentiate jumping power.

3. Despite potentiation of jumping power, the actual jump height was not augmented by any of the PAP protocols. This was attributed to the possibility of a fatigue effect.

Strength, Limitations and Future Considerations

1. They studied an elite athlete population, which is rare and significant.

2. The conclusions confirm how difficult it is to study PAP in a real-world situation with scientific rigor.

3. The fact that potentiation occurred in certain parameters of the vertical jump such as power and velocity but not the actual jump height may question the relevance of the findings to athlete performance. Nevertheless, this remains an important area of study for the high performance athlete and this study adds to our overall understanding.