There are several variables that coaches have the option to monitor when it comes to tracking fatigue and training status in their athletes. Though it can get quite complex and sophisticated, we can categorize monitoring variables into three groups listed below with a brief list of examples for each:
- Heart rate variability (HRV)
- Heart rate recovery
- Hormones (testosterone, cortisol)
- Inflammatory Markers (C-Reactive Protein)
- Muscle Damage (Creatine Kinase)
- Wellness Questionnaires
- Mood State
- Perceived Training Load (session rating of perceived exertion)
- Psychomotor speed (reaction time)
- Maximal vs. Sub-maximal/Non-fatiguing
Performance tests tend to be the preferred monitoring variable, particularly for coaches and teams with minimal budgets. This is because it is cheap, simple and relatively effective. Maximal performance tests such as 1RM back squat, fitness tests (Yo-Yo, beep, etc.) can only be evaluated periodically to assess the effectiveness of a program (among other reasons). These are not practical for routine monitoring to assess fatigue and training status. Non-fatiguing performance measures such as vertical jumps, sub-maximal bar velocity, 10 m dash, etc. are more appropriate for weekly or more frequent monitoring. However, there are concerns as to the sensitivity of these tests for detecting early signs of fatigue that can progress quickly if not managed. This can be particularly concerning during the in-season.
A recent study published ahead of print in the Journal of Sports Medicine and Physical Fitness evaluated athletes throughout a week of normal training, intensified training and during a recovery week consisting of reduced training. Psychological (profile of mood states) and physiological (testosterone, cortisol) were assessed before the training program, 3 times per week throughout and post-training. Additionally, performance parameters were evaluated once per week.
The results showed that intensified training significantly altered mood states and decreased the athletes desire to train while returning to baseline values after the recovery week. Resting testosterone concentrations significantly decreased and exercise-induced cortisol responses were diminished during the intensified training week. Interestingly, these endocrine markers remained altered following a week of reduced training loads. Performance parameters did not change despite changes in training quantity.
This study provides support for the idea that performance testing may not be as sensitive of a monitoring variable as we may like it to be. It appears that other physiological and psychological parameters will respond first and that performance can be reasonably maintained in the presence of fatigue. Therefore, excessive fatigue may have accumulated by the time performance markers detect meaningful changes. Coaches should consider tracking other variables (i.e., wellness) to keep tabs on fatigue accumulation in athletes.
Kageta, T., Tsuchiya, Y., Morishima, T., Hasegawa, Y., Sasaki, H., & Goto, K. (2015). Influences of increased training volume on exercise performance, physiological and psychological parameters. The Journal of sports medicine and physical fitness.