Fitness & Fatigue: How to Interpret Fitness and Fatigue Scores

What is my fitness and fatigue score? 

Derived from the acute and chronic training load theory, which is an established concept to monitor external training load; your fatigue (acute) and fitness scores (chronic) represent your recent and historic swim training, respectively [1]. Fitness and fatigue can then be used to calculate your training form score.

Fitness: Your fitness score combines the duration and intensity of your swims from the past 42 days to represent your chronic training load on how much you have trained historically. Exponentially weighted averages enable the fitness score to represent your training of the past 3 months [2].

Fatigue: Your fatigue score, on the other hand, combines the duration and intensity of your past 7 days to provide you with insight into your acute training load for how much you have trained recently. Exponentially weighted averages enable the fatigue score to represent your training of the past 2 weeks [3]. 

These scores, important measures of your external training load, can be used to monitor how you are tracking with your swim training. As your training focus may differ across timepoints, the fitness and fatigue scores that you produce will differ. 

What do fitness and fatigues tell me? 

Fitness and fatigue will enable swimmers and coaches to prescribe and overload stress on the body in a progressive and safe manner to reap the benefits of training adaptations, without accumulating too much fatigue that you enter a state of overreaching. Overreaching to some degree is necessary to improve fitness, however, when taken too far, without adequate recovery, puts swimmers at risk of overuse injuries, illnesses and if untreated, overtraining syndrome [4][5].

Often times, coaches will aim to progressively increase your chronic training load (fitness) to steadily and safely build to improve your swimming endurance [4][6]. If training intensity (training stress score) jumps too high or too quickly, we put our swimmers at risk of overtraining syndrome and you may see symptoms of high fatigue, poor performance, lethargy, and disrupt our motivation and attitudes towards swim training [4][7]. 

How is my fitness and fatigue calculated in Simma? 

Fitness:

Fitness score = fitness today ≈ 0.0465 x stress today + (1-alpha) fitness yesterday

Fatigue: 

Fatigue score = fatigue today ≈ 0.25 x stress today +(1-alpha) fatigue yesterday

How to view my fitness and fatigue in Simma? 

Click on "Progress" in the top left of your screen (if on Simma Web) and bottom of your screen (if on Simma App), and scroll down to see your fitness and fatigue, alongside your training stress scores, across your recent training history. 

Simma Web

Simma App