Over the last 30 or so years, altitude and heat training has become a big topic that has been discussed within the Exercise and Sports Science community. It is one way that coaches can add variability to a program. I know that at the beginning of every year my running group heads to Jindabyne for some squad bonding and stories to create that we’ll talk about in subsequent training sessions.
Whilst in Australia you cannot really train at altitude (in comparison to beautiful places like Colorado), training in the heat is a big thing that occurs over our harsh summer days. There have been some sessions where I can recall training in 40℃ +. These kinds of sessions can be rough, potentially some of your hardest training sessions completed in the year.
So today’s blog is going to be all about training in the heat and some considerations to look out for before running in some of those extreme temperatures.
The benefits of training in the heat -
Before the 1968 Mexico city Olympic games, it has been said that almost every Olympic athlete travelled to the games 3-4 weeks prior to the opening ceremony and competition. The reason behind this was due to an excellent process known as acclimatisation. This is where you train in certain conditions, so that you are able to perform at your best under those said conditions. In this example, heat/altitude and how the body manages this was of great concern for athletes competing at those games.
This is where big competition benefits can come from in the running world. By training at similar temperatures, at similar times of the day (respective to your race), athletes are able to optimise their sessions and performance under the said conditions. Although sometimes it might be unrealistic to train around the specific time of your scheduled race (e.g. scheduled start at 10PM), the conditions (weather wise) that would most normally be observed around this time can still be trained under. There are many ways to complete this, however, for those summer competitions it is best to train in the heat to get your body ready for racing in the heat.
Physiologically, there are benefits from training in the heat. For instance, a study by James et. al (2016), showed that training in hot/humid conditions over a relatively short period of time (5 days the study went for) was able to improve 5000m performance much more than compared to the control group, believed to occur due to the increase in VO2max and running economy that was also observed at the end of the study. It is important to note that submaximal VO2 achieved pre-test and during the trial was lower compared to control. The higher results were achieved when athletes completed the post-test assessment at room temperature for the trials.
Even in winter, you can still put yourself under heat conditions to further improve performance. A study by Dorson and Morton (1989) showed that similar running-related benefits were observed when participants trained in either hot conditions, or wore warmer clothing in cold climates when compared to the control group, potentially due to increases in “blood plasma expansion.” This was with respect to no increases in “fitness,” so the running economy might have been altered for both groups during the study.
But aside from the body, training in the heat can also help with your mind. Training & racing in the heat can impact you psychologically just as much as it can physiologically. If you avoid these kinds of scenarios, your mind might not be able to “cope” as well as you thought previously, especially as this would be the first time, in a while, your body (including the mind) would be trying to run through the harsh Summer heat.
You might think that you are capable, but you can really learn what can happen once you start training and start acclimatising to the heat.
Both the physiological and psychological benefits that come from heat training are apart of the acclimatisation process, but are still important factors to consider and the role they play in this process during training and races.
Considerations for heat training -
Like anything in life, it has to be done in moderation and has to be done right. If you do not account for the physiological changes that occur during heat training, you will not achieve these benefits in performance. The largest changes during a heat training session (based on the studies outlined) include: decreased submaximal VO2max, increased heart rate, increased sweat rate and lactate threshold (just to name a few). With this are two considerations/strategies that need to be taken into account for when training/coaching in the heat.
Children - It has been well noted that children/early adolescents tend to have an altered thermoregulatory system. This means that their body isn’t able to accomodate for the physiological stresses that come about from different weather conditions. It is why some kids can wear a singlet in the middle of winter and not complain about how cold it is.
This is extremely important to consider when training in the heat. If you can’t adequately remove excess heat, then your body is going to try and stop you from running at your desired intensity, which impairs performance. In the case of children, as a coach you’ll need to make sure your athletes are “Sun Smart” which I will go into a bit more detail shortly.
Sodium/water loss - Although there are recommended guidelines for drinking water for the general population, for runners it's a bit more complicated than that. This will be individualised, because there are some people (like myself) who sweat an entire ocean out of their body, others can not really sweat at all and everyone else in between. This can also be dependent on the duration of your session and the intensity of your session.
Sodium/water loss is important for runners, because of the effect dehydration has on the body. We all know that dehydration affects our performance in more ways than one, but what some of us forget is that sodium also helps us out. Whilst most of us already consume more sodium than the recommended guidelines (400mg/day) due to the takeover of processed foods in our grocery stores and table salt, sodium is important in the production of energy and muscle function. A lot of sodium can be present in our sweat, depending on the individual, which could alter how we perform during a session of race. Therefore, it is important to consider and account for this when running in the heat.
Being Sun Smart in the heat -
In order to account for these considerations that need to be looked at when training in the heat, being sun smart is essential. Wearing a hat/appropriate clothing, warming up in the shade, bringing a lot of water (or having access to a water tap), sunscreen… these are all little things that can help target these considerations when training in the heat. We all want to perform at our best, particularly with sodium/water loss, it is important to take this seriously within your training program. For some children, it might be more beneficial for the coach to prescribe more rest in between reps, or reduce the total time of the session.
When undertaking your long runs, a good tip is (pre run) weigh yourself, and compare this post run. The amount of weight you have lost equals how many litres of water you should consume. For example, if I lose 2.2kg of body weight during my long run, I should drink 2.2L of water within a few hours post run.
In terms of your shorter, but quality and high intensity, sessions, I recommend to ensure that adequate water and possible sport drinks are on hand, especially if you lose a lot of sodium in your sweat. Sports drinks might not work for everyone, especially if you have a “sensitive” stomach. I recommend you talk to your coach and/or a medical professional about consuming sports drinks during a training session. It might not be for you, or not benefit you at all.
Hopefully I have taught you a thing or two about training in the heat and strategies that can be implemented in order to account for the considerations that are evident.
Remember that this all has to be individualised. Although there are general trends in how our body responds to heat, the extent to which that is expressed is different from person to person. Therefore, what specific strategies you implement will have different effects on your body and performance.
Keep up the running,
James, C. A., Richardson, A. J., Watt, P. W., Willmott, A. G., Gibson, O. R., & Maxwell, N. S. (2017). Short-term heat acclimation improves the determinants of endurance performance and 5-km running performance in the heat. Applied Physiology, Nutrition, and Metabolism, 42(3), 285-294.
Dawson, B., Pyke, F. S., & Morton, A. R. (1989). Improvements in heat tolerance induced by interval running training in the heat and in sweat clothing in cool conditions. Journal of sports sciences, 7(3), 189-203.