by Alex Cross
Working in a sports medicine clinic, one of the main things we do in rehabilitating injuries is assessing and managing/altering training volumes. This process of ‘load management’ occurs across all levels of the athletic population, from professional to the everyday active individual. As we emerge from lockdown, the management of activity volume is as important as ever, as increases in training load can place undue stress on the body, and ultimately lead to an overuse injury.
What is overtraining?
Often, the goal of training is to increase fitness, strength and performance. Improved fitness and performance is generally achieved through progressively increasing training loads and exercise complexity – however, these increased loads are only tolerated when accompanied with structured periods of rest/recovery and training (this process is called training periodization)1. Thus, overtraining is when there is an accumulation of training load that the body does not have the capacity to cope with (demonstrated in Figure 1)1. Importantly, it is not just overall training volume we must consider when looking at potential overload, other variables we may manipulate are outlined in table 1.
Table 1. Training variables which can be manipulated
Frequency
Total number of sessions per week
Intensity
Level of effort within a training session, relative to somebody’s maximal effort
Volume
Total workload per training session *Can also relate to total workload across the week
Up to 60% of athletes will experience some form of overtraining during a period of their performance schedule, and the injury outcomes of this overload will range in severity2. It is a fine balance, as working to improve your fitness requires pushing the limits of one’s body, however, pushing too hard can be detrimental. This is why it is great to check in with your coach and/or physio regularly during your training to ensure that your loads are at an optimal level.
Figure 1. Workload v fitness (https://trailmag.co.za/wp-content/uploads/2015/08/Adrenal-Overload-over-training-graph-t17.png)
Growing children
It is important to recognise that many children and adolescents may have grown a significant amount during lockdown. Combined with this rapid growth, immature skeleton and lack of normal structured exercise/sport, children are at a much higher risk of experiencing growth and/or load related injuries. With this in mind, it is important to gradually re-expose children back into their normal loads and trainings in order to sustainably return them to normal levels of activity. So, if your child has done little over the last three months, don’t go back to do everything in the first two-four weeks, rather gradually add one or two sessions in per week until they return to their normal level.
Overtraining and injuries
The relationship between overload and injury is quite simple, if there is insufficient recovery and capacity to tolerate the increase in load, then the likelihood of sustaining an injury skyrockets3. The most common injuries related to overload are – tendinopathies (irritation of tendons – most commonly achilles and patella), stress fractures/reactions and muscular overload3. The specifics of the pathology differ from injury to injury, but in all cases it boils down to a failed healing response to the load placed on the structure – bone, muscle or tendon. When intensity or load are too high and there is inadequate recovery, this can cause a breakdown in cells within the body and increased injury risk.
There are differences in why the healing response is more successful in some individuals rather than others, and we have varying levels of control over these factors. For example, hormonal and molecular levels can affect how the body responds to insult, which automatically predisposes and individual to a higher susceptibility to overload4. Training and injury history is another factor which can either protect or predispose to overuse injuries. Nearly everybody will experience a niggle of some sorts whilst training, what is important is recognising when it is not settling as it should, as this is generally the start of an injury cascade. Once you do start to experience some discomfort, this is a good time to consult with your physiotherapist or coach about how to modify your program to ensure you continue to maintain fitness and prevent injury.
So how do you avoid injuries with over training?
Rest and recovery are paramount – ensuring that you have adequate rest in between training sessions is critical, as this lets the body replenish its stores and the healing process to occur. Little things in recovery such as slow walks, foam rolling/stretching, nutrition and sleep are also very important, particularly in the injury rehabilitation phase. Having a rest day every week is a good place to start.
Easy sessions are just as important as hard sessions – having easy sessions in your program is important to help the body acclimate to load and facilitate improvement on a molecular level (oxygen transport, mitochondria density etc.). If all your sessions are at 100% intensity, the body will not have the capacity to constantly go through the healing response.
Have the right program – work with somebody you trust (coach, physio) to help design your program and make sure you are constantly feeding back about how it is going. Programs should not change in volume by large amounts week to week, and thus working with a qualified professional is important to ensure volume levels are at an appropriate level.
Listen to your body – if you feel like you need a rest day or need to back off, you are probably right. Getting onto things early can lead to much better outcomes.
References
Kreher, J. B., & Schwartz, J. B. (2012). Overtraining syndrome: a practical guide. Sports health, 4(2), 128–138. https://doi.org/10.1177/1941738111434406
Kreher J. B. (2016). Diagnosis and prevention of overtraining syndrome: an opinion on education strategies. Open access journal of sports medicine, 7, 115–122. https://doi.org/10.2147/OAJSM.S91657
Aicale, R., Tarantino, D., & Maffulli, N. (2018). Overuse injuries in sport: a comprehensive overview. Journal of orthopaedic surgery and research, 13(1), 309. https://doi.org/10.1186/s13018-018-1017-5
Wenner M. Inflammatory clues. Sci Am. 2009;301:24–26. doi: 10.1038/scientificamerican1209-24.
Falk Neto, J. H., Parent, E. C., Vleck, V., & Kennedy, M. D. (2021). The Training Characteristics of Recreational-Level Triathletes: Influence on Fatigue and Health. Sports (Basel, Switzerland), 9(7), 94. https://doi.org/10.3390/sports9070094