Fit for 90: Understand stress-adaption response to get most of your players (VIDEO)

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Fit for 90: Understand stress-adaption response to get most of your players (VIDEO)

Editor’s Note: Dr. John Cone, founder of Fit for 90, explains how coaches can get the most of their players by first understanding stress-adaption response. As the Official Player Monitoring System of US Club Soccer, Fit for 90 is helping to advance the Players First pillars of Coaching Development and Player Health & Safety.

We talked last time about using the logic of sports science to problem solve soccer-specific physical development in the same way we solve technical and tactical problems. This time I’d like to apply similar logic to a core element of physical training, the stress-adaptation response.

The importance of this concept cannot be understated: it is the difference between optimizing performance and player development versus over-training and injury. It is a principle that must be understood by youth and professional coaches alike, and is the pervasive principle in our planning of training – also known as periodization.

The stress-adaptation response may be broken down into a series of simple and logical concepts:

  1. The player walks onto the field each day with a finite amount of energy (training readiness) and a given performance level that is specific to their training background. Both are unique to each individual player and something that we will discuss in detail in future articles.
  2. The training session that we run stresses each player differently and are specific to the overall demands (load) of the session and the type of work performed.
  3. The stress of the session results in a decrease in a player’s capacity and performance – also known as fatigue.
  4. Fatigue experienced is relative in severity (depth of the curve) and duration (length of the curve) to the physical stress (i.e. overall load and type of stress).
  5. With time, the athlete recovers and then adapts to the stress experienced.
  6. The adaptation to stress ultimately leads to an increased performance level relative to the initial session.

Balancing training stress with adaptation requires the coach be prepared each training day with the knowledge of:

  • The overall readiness of the team to train or compete
  • Any individuals or groups of players who are outliers relative to the team

The goal of the coach is to match the team’s readiness to deliver a session of equivalent demand. Additionally, the coach must also be prepared to address the individual player’s readiness by adapting training as needed to manage the individual within the team. Simply:

  • High readiness equates to the ability of the players to perform more work (higher total load) at a greater intensity.
  • Low readiness equates to the ability of the players to perform less work (lower load) at a lower intensity.

The result is that for each level of readiness a training load target may be developed, with the coach able to confirm how well they hit the mark by quantifying the stress experienced by the players in any number of ways.

The next article from Fit for 90 and Dr. John Cone will discuss the timing of training stimuli relative to the stress-adaptation response, and the additive effect of the stress-adaptation response to maximizing performance, development and injury prevention.


As the Official Player Monitoring System of US Club Soccer, Fit for 90 delivers an integrated player monitoring system assessing athlete readiness and physical training stress. US Club Soccer members may purchase licensed access and use of the Fit for 90 platform at a price of $110 per month over 10 months ($1100/year) per team (regularly $2,000).

Dr. John Cone, the founder and CEO of Fit for 90, has extensive experience playing and coaching at the youth, collegiate and professional level. Dr. Cone’s background as a sports scientist, coach, and educator gives him the unique ability to bridge the worlds of science and sport. John holds his U.S. Soccer Federation ‘A’ license, is a certified strength and conditioning coach (CSCS), and the only American holder of the esteemed FA Fitness Trainers’ Award (2004). Dr. Cone has been both a coach and director of sports science in the MLS. Dr. Cone, and has over 100 seasons of experience as a soccer-specific periodization and sports science expert working with teams from youth to professional levels of competition.