Is Heat Training The New Altitude Training? Get Out In The Sun If You Want To Boost Performance, A Primer.

Is Heat Training The New Altitude Training? Get Out In The Sun If You Want To Boost Performance, A Primer.

NOTE: This article originally appeared on the blog of Thanyapura Sport Resort Phuket, partners of WTW where we contributed to their content. You can check them out here, and please use our name if you book a visit for discounted rates 🙂 

Many elite sporting events occur during summer months in warm climates. How much attention and focus is put into preparing for these conditions? A few extra electrolyte tablets placed in the lunchpack? Showing up a week early to the race place to adjust? Why not spend a training camp, training cycle, or even a proper season in a warmer climate? From the Brazilian World Cup to the Kona World Championships, chances are you are headed to an event where the sun will be shining sometime soon. How are you preparing? Here’s a secret: Preparing IN hot conditions of the race may enhance your training more efficiently and is far more feasible than other methods you may have been using previously.

Folks have been hooked on altitude-based (hypoxic conditions) training ever since stories of one Lance Armstrong sleeping in an altitude-chamber tent came out of the hills of France in the mid-2000s. Deprivation of oxidative conditions enhances physiological adaptations especially through increased oxidative capacity leading to possibly increased VO2Max and even lactate threshold measurements (Bailey 1997). What could go wrong? Well, hypoxic training is a pain in the butt! Do you want to own a tent, wear a mask (which doesn’t work, by the way) or have to travel to or even live at elevation in order to maximize training adaptations?

What if there was an easier way to take advantage of available environmental conditions to make the most of your training and improve your performance in all conditions?

While it has long been known that repeated exposure to a hot environment produces adaptive responses which reduce the physiological strain your body experiences in heat exposure (Armstrong & Dzaidos 1986), hype about utilizing heat as a training tool really ramped up in 2010. University of Oregon researchers found that a ten-day training camp in heat conditions lead to a 5% increase in VO2Max among trained cyclists. Short Term Heat Acclimation (STHA) became well-known, and ever since then, the scientific and high performance community has had it’s eyes keenly tuned in on the effects of training in the heat as an potentially optimal (and more feasible!) environmentally-induced performance enhancer. Paying attention now? Good. If you are sick of abandoning your family to train up in the mountains? Tell the kids to jump in, it’s time to go on vacation somewhere sunny and find somewhere HOT to train.

Elite endurance sport is played out at very fine margins, and the scientific literature is showing heat-training to be a confident method for attacking these margins: a 2012 study out of New Zealand investigated Rowers doing very light training in serious heat (40-60 ºC) conditions resulting in a 1.5% improvement in 2000m performance! These are in athletes already making the very most of their potential. How much might you improve by training in the heat? Just this summer, a review in the Journal of Sports Medicine (Chalmers, Esterman 2014) discussed eight major studies recently investigating Short Term Heat Acclimation (STHA) training and how it can improve sporting performance, so heat training is here to stay! This three-part series investigates both the why and how of STHA training. As a primer, here are a few physiological factors which are at play:

Plasma Volume Adaptations

It’s commonly known that a primary upstream benefit of training in hypoxic conditions is the instigation of Red Blood Cell (RBC) production in the body (Cymerman et al 1989; Ashendon 1998; Bailey 2000; Hahn, Gore 2001). This is certainly and obviously useful but of potentially equal significance is the Blood Plasma Volume (BPV) increase which occurs from training in heated conditions (Geor, McCutchen 1998; Wendt, Van Loon 2007; Holm et al 2012; Bergeron, et al 2012). Various studies in the literature have shown heat training camps (of 5-10 days) to increase blood plasma volume by between 4-7% (Sandstrom et al 2008; Lorenzo, et al 2010; Garrett, et al 2012;). This results in a higher VO2max at any given effort level, meaning more power production for you! Keep in mind that while RBCs are essential for delivering oxygen to working muscles, those muscles won’t function maximally if you are dehydrated during an event, and blood plasma is what keeps tissues hydrated and shuttles around those ever-important electrolytes in the first place (Maughan 2007). RBC/BPV? Equal players! More on that below…

Dehydration Makes The Body Adapt–Allow For Stress!

A dehydrated body DURING a race is one which will not function optimally. However, what about during training? It’s become all too common to go to extreme lengths to not allow discomfort during or after a session. Super recovery is an admirable goal (discussed below) but is not always useful. You’re probably familiar with the train-low-compete-high method: Train with low muscle glycogen (i.e. don’t eat before training) to increase adaptations, and when on race-day you’ve eaten before training, you’ll feel and perform great! The same concept applies to nearly any aspect of performance and adaptations, and hydration status is one such aspect: If you are always perfectly hydrated, your body will adjust poorly if it becomes dehydrated on race day. Hydration management is one of the most-emphasized aspects of preparation for competitions in the heat, and for good reason: studies have shown the top placers in endurance races to often cross the finish line around 3-5% of their body weight dehydrated (Sharwood et al 2004; Wharam et al 2006; Zouhal et al 2011) Fluid regulatory hormones such as Heat Shock Protein 70 (HSP70, detailed in the next article!) can be greatly impacted by STHA training. Therefore, if the training bout is short and careful, leaving the water bottle at home during a training session under the sun can be a simple but effective way to prepare your body to deal with hot racing conditions.


Comparison of a few popular heat training destinations (Kona & Phuket) vs big metropolitan cities such as London and Sydney.

Combine Methods, What Is The Point Of This Session?

Many different methods can and should be used to increase your training adaptations, but the question remains how to combine them all? There is no one sure answer, but the literature and patterns of elite athletes suggest some ideas: Train in hypoxic conditions to increase RBC and other cardiovascular adaptations, then train in heated conditions to enhance cardiopulmonary, osmoregulatory and thermoregulatory systems. In preparation for sports and race events, remember: specificity rules. Think about what you need to prepare for and mimic those conditions! Furthermore, always ask, what is the point of this session? There is a time and place for taking extra care to recover immediately, maximally and to prepare for the next session. There is also a time and a place for instigating a stimulus to create an adaptation and elicit increased capacity for performance. Simply put, sometimes you need to beat yourself up to become stronger. Most endurance athletes don’t have any problems beating themselves up, but many also take too much care and create an environment which is more conducive to allowing hard training the next day than eliciting a proper training adaptation…which are you aiming for? If you want to fit a lot into the week, plan and recover accordingly. However, if you wish to create a maximal adaptation and increase your body’s ability to deal with anything and perform under any conditions, throwing yourself very carefully into those conditions may be the best way to maximize your potential for performance!

In the next post of this series you’ll learn how to adjust to heated conditions and the mechanisms behind how your body learns to deal with it’s environment. Stay tuned! In the meantime, Click Here to Subscribe To Our Mailing List