Return-to-play – Internal vs External Load



In order to understand the efficiency of starting players, one team collected baseline measurements of external load and internal load (a measurement of muscle output) at the start of the season. After a few weeks, one player suffered a quadricep injury and needed to recover.

As the player started return-to-play protocol, the team asked STRIVE  to re-assess his efficiency. The goal was to replicate the pre-injury practice session and identify any significant changes that could impact his recovery.


Before the injury, the player was found very efficient likely due to his conditioning to recovery balance. When STRIVE re-assessed the player post-injury, it showed that the internal load drastically increased even though the external load stayed consistent causing his efficiency to decrease nearly  40%.

Player’s Efficiency and Fatigue during practice


  • External Load:  402

  • Internal Load:  302

  • Efficiency:  1.33 (External Load / Internal Load)


  • External Load:  404

  • Internal Load:  772

  • Efficiency:  0.52 (External Load / Internal Load)

Screen Shot 2019-04-25 at 9.58.51 PM.png


This insight showed coaches that even though the player was able to participate in practice, his muscles were overworked in order to speed up his return-to-play timeline. As a result, they implemented more prescriptive recovery sessions to reduce the chance of re-injury and safely return the player to 100% participation.