Training Volume and Triathlon Performance
Endurance athletes tend to train a lot, particularly in triathlon. Obviously, the term “a lot” is very relative as five hours of training a week might feel like a lot for a novice or untrained endurance athlete, whereas more advanced and well-trained athletes might feel like 20 hours a week is a lot. However, triathlon is a sport that typically breeds high training volumes due to the need to fit in swim, bike, and run training each week. Long-distance triathlon training (i.e., Ironman and Ironman 70.3 racing) typically demands the greatest training volume due to the length of the competitions.
It is not uncommon to see some professional long-distance triathlon specialists training upwards of 30-40 hours per week during heavy training. For amateurs, it is not uncommon to see 20-hour training weeks during peak training for an event. There seems to be this pervasive notion amongst triathletes that more training is always better and will yield better performance and higher fitness levels. However, is this always the case? Is greater training volume always better? Let’s dive into some recent research to help provide some answers to these questions.
Self-Reported Training Volume and Ironman Performance
A recent (published in 2021) study by Sinisgalli and colleagues enrolled 99 age group triathletes (80 men, 19 women) that were participating in the 2019 Ironman Brazil. The researchers enrolled these athletes, had them complete an online questionnaire ~40 days out from race day, and then recorded their overall race time as well as individual swim, bike, and run split times from their performance. Within the questionnaire, athletes were asked questions related to weekly training volume, previous Ironman racing experience, nightly sleep duration, and about signs and symptoms related to overtraining (unintentional weight loss, perceived decreased performance, loss of energy/feelings of fatigue). Researchers were looking at relationships between these self-reported variables and performance in the 2019 Ironman Brazil race.
The following are perhaps the most interesting findings from this study:
1. Total race time as well as individual swim, bike, and run times were not significantly different between those that trained up to 14 hours/week, between 15 and 20 hours/week, and more than 20 hours/week. In fact, although it was statistically significant, those training the most actually had slightly slower overall race times.
2. Triathletes that reported overtraining-related symptoms (unintentional weight loss, loss of energy, feeling of decreased performance) did significantly worse (slower race times) than those that did not report these symptoms.
3. Triathletes that has previous Ironman-distance racing experience did significantly better (lower race times) than those that did not.
So, what do these findings teach us? First off, greater training volume isn’t always better. This study certainly has its limitations, primarily it’s self-report and correlative nature. Due to the study design, researchers could not establish a cause and effect relationship between training volume and performance as researchers only had self-report training volume from one point in time to relate to a single race performance. However, the findings here offer up a discussion that is important for all endurance athletes to have and to understand.
First, greater training volume might lead to better performance IF the athlete can adequately recover from that training and if the increased training volume is approached sensibly. In other words, if an athlete sacrifices sleep to get in more training, this will likely lead to worse performance. If the athlete also increases training volume too rapidly and does so by doing more intensity as well, it may also lead to worse performance. Building into greater training volume should be a gradual and slow process, starting with the addition of very easy and low intensity training. Training volume increases should only go so far as the athlete can tolerate and recover from. Otherwise, this greater training volume may not lead to greater performance and may ultimately impair performance and lead to overtraining.
Second, speaking of overtraining, those athletes in this study that reported overtraining-related symptoms also fared worse in their performance than those that did not. Overtraining syndrome is a complex and multi-system issue that usually deals with detrimental changes to the nervous system, cardiovascular system, musculoskeletal system, and immune system. We have no idea if these athletes had a diagnosis of overtraining syndrome in this study as this was not asked, but some of the most prominent symptoms related to overtraining, also some of the biggest warming signs, are unintentional weight loss, feelings of lingering fatigue and an overall loss of energy, and decreased performance. Those that reported these symptoms about 40 days out from Ironman Brazil ended up performing worse than those that did not.
Overtraining and related symptoms are something that endurance athletes should be very aware of and should monitor regularly. If an athlete notices any of these warning signs, then rest and recovery should ensue immediately. Overtraining syndrome usually develops over months and months of ignoring these warning signs and thinking that they are part of the “normal” training process. Many athletes, particularly those that train for long-distance triathlon, think that feeling exhausted and beat up all of the time is part of the process. Some fatigue and soreness here and there are completely normal, but constant fatigue, constant soreness, reduced performance capacity, and abnormal heart rate responses to training and at rest are not part of the normal training process and should not be ignored if they are present. Overtraining syndrome is something you will want to avoid with a passion as it can take months or years to recover from. Some professional athletic careers have been ruined and terminated prematurely due to overtraining, so don’t tread lightly with this topic.
Finally, athletes in this study that had previous Ironman experience did better. This could be due to many factors like greater number of years training. However, it is interesting to note that experience usually helps athletes improve as they learn how to better fuel during training and racing, how to train smarter, and also from the accumulation of years and years of training stress. Endurance sports favor those that train smart and consistently for years and years, not necessarily those that train really hard for short periods of time. Furthermore, it will usually be detrimental to train really hard too often as this can lead to overtraining syndrome and ultimately reduced performance (see some of my previous posts on polarized training intensity distribution).
Training volume and training intensity, although intensity was not discussed as much herein, are both very important to monitor with triathletes and endurance athletes more broadly. Coaches and athletes alike can sometimes get caught up in carelessly doing more and more in the hopes that they will get fitter and perform better. Some of this is driven by misconception, some of it driven by the need to look “epic” on social media. However, the best training approach is one that is smart, one that takes into account adequate recovery from training, and one that is sensible in terms of training volume and intensity. Doing more than one can handle for long periods of time will likely not yield better performance and can have very negative consequences in the long run.
1. Sinisgalli R, de Lira CA, Vancini RL, Puccinelli PJ, Hill L, Knechtle B, Nikolaidis PT, Andrade MS. Impact of training volume and experience on amateur Ironman triathlon performance. Physiology & Behavior. 2021 Apr 1;232:113344.
Happy training and racing!
-Ryan Eckert, MS, CSCS
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