Training and Racing in the Heat

It’s moving into summer down under and the temperature is starting to edge its way into the uncomfortable realm with a high of 30 degrees on my ride today. Kona has come and gone and with that excitement we got a number of heat based questions via our weekly Foot Traffic facebook Q and A session. So it was quite fortuitous to be at a sports science summit where two presentations in particular focused on rehydration after exercise and the effects of heat on performance.

I’ll start with the effects of heat on performance because that seems to be a logical place to start. We have probably all experienced the energy sapping effects of heat at some stage during our training and racing and alongside this understanding there has been a lot of discussion around core temperature. In science we often measure the core temperature as a more accurate way to assess the heat stress on the body. As a result slushies had a brief feature in the endurance communities collective conciousness but one thing we found was that it’s hard to keep a slushie a slushie when you’re out on the bike in greater than 30 degrees for 4+ hours. I found a fantastic bottle in 2014 when I was on the Big Island that managed to keep the blocks of ice I put in it frozen for almost the entire ride which was bliss because water always tastes nicer cold but the volume of the effect of that internally applied cool fluid compared to the amount of externally applied fluid was pretty minimal.

The talk of interest was an AFL study (because Australians interestingly drop a lot of money into improving the performance of a sport who no one else in the world plays) but the previous work that he talked about was in fact done on cyclists because with cycling its pretty easy to get a similar sort of training scenario in a lab setting and we can thrash cyclists for quite a bit longer than other athletes. The key finding of one particular study where cyclists were allowed to cycle at their self-selected pace, was that when the difference between the core body temperature and the skin got smaller then performance decreased.

Your core temperature is going to heat up when you exercise, because our muscles are quite inefficient in their energy usage, and we use a variety of modalities to cool ourselves down. All modalities require pumping the hot blood from the centre of the body out to the skin to cool down. With sweating, the energy used to evaporate the water off your skin cools the blood at the surface of the skin which can then be pumped back towards the core and hot blood replaces it. Another, less effective method of cooling, but one that is relied on a bit more heavily in post-menopausal females, is conductive cooling, which relies on a heat gradient between the skin and the layer of air in close contact with your body. If the air is cooler then heat energy can be lost to the air from the skin effectively cooling the blood. If the air is moving around us or we are moving through the air then this layer of air is replaced by cool air increasing the efficiency of this process, however if the air is still then a convective process replaces the hot air at the surface of the skin with cooler air. Conduction is not nearly as effective as evaporative cooling, which is why we sweat and dogs pant.

Think back to that studies conclusion, reducing the gradient between the skin temperature and the core temperature results in reduced performance. Which makes sense if the skin is our conduit for heat loss, then the cooler the skin is relative to the core temperature the more heat loss we will be able to achieve

In a humid environment like Kona, or in my case the Gold Coast in summer, the air is already saturated with water and so evaporation doesn’t work so well, once you have 100% saturation no more water will fit in the atmosphere and so evaporation stops happening altogether and you usally get rain.

Which brings me to an observation one of the Foot Traffic athletes made regarding the Pro-race in Kona. It appears there was a greater application of fluid externally than internally. Don’t get me wrong internal fluid application is important to try and offset the dehydration effects of sweating, and in Kona this will be worse because the body will try and sweat more as your body heats up to try get some relief but the evaporation isn’t working. The external application of water can assist in two ways. If it’s humid and evaporative cooling isn’t very effective, applying cool fluid to the body will help to reduce the skin temperature, it’s why ice cold sponges on the run feel so good. If it’s not as humid then the external application of water can replace the sweat, it is evaporated off the skin and results in cooling of the skin. In both cases, the skin is being cooled and that gradient between skin temperature and core temperature is increased.

I’ve been in races where people come across the finish line complaining about the sprinklers and hoses the locals have out on the run because they get blisters. When I see a hose, blisters be damned, I’ll take the cooling any day. It feels good and there is a reason it feels good. Things your body doesn’t want you to repeat feel bad, things that are good for your body feel good. Your body in it’s own way is telling you to get some more of it because it’s beneficial to you.

So how does all of this lead to a performance decrement? Well the leading theory is currently that, the lower the gradient between the skin and the core temperature, the more blood is pumped to the skin, but the skin is less effective at cooling this blood down and so it kind of pools in the skin (we have complex regulatory networks of blood vessels in the skin which allow more blood into the skin in hot circumstances). If there is more blood hanging out at the surface of the body there is effectively less blood going to your lungs for oxygenation and back to your heart for pumping to the muscles. A descrease in stroke volume is observed (for the science geeks). Or a decrease in blood going to the muscles to do work.

So how do we improve performance in the heat. That goes for training and racing, because even in training we are looking at pushing the body to new limits. Keep the skin as cool as possible and then your body will cool itself down.

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To eat or not to eat, that is not a question

Because I’m in the throws of planning a nutrition session for the Saint Kentigern College Cycling team and coming off the back of some female specific seminars, I figured a nutrition post is probably in order.

It was a while back that I was having a discussion with a fellow Foot Traffic athlete. They are data mad and was describing the very real struggle they have post training. Do I shower, upload my data or eat first?

There should however be no question. Always, always, eating should be the top priority. Replacing any energy deficit you may have built up (more about this later) but more importantly, getting the important nutrients (protein and carbohydrates) to the muscles you have just worked so they can start the repair and recovery process as soon as possible.

The aim of training is to get stronger and therefore faster. The way in which this occurs is that we stress the body, specifically the muscles, bones and cardiovascular system, just beyond what it is capable of. This shocks the body a little and tips the seesaw slightly out of balance. The key here is ‘slightly’. Small changes in balance within the body trigger a cascade of responses resulting in the body adapting to meet the new level of stress that it has encountered. If you push the seesaw too far out of balance, however, or don’t allow it to adapt and accommodate adequately before introducing the next round of stress then the seesaw leans further towards injury and illness and the further over it tips, the more rapidly it descends towards these less than ideal outcomes.

So how soon after training do I need to eat? Within 15-30 mins but the earlier the better, and for females that 15 minute mark is even more crucial than for males. But remember you then need to have a proper meal within the hour.

What should I eat? Something high in fast absorbing proteins, particularly leucine. Whey protein powder is probably the best source as it is a rapidly absorbing protein but if you are vegan or allergic then plant protein sources are fine but you need to take about 50-60 g compared to the 30 g you need of whey protein. Branch chain amino acids or BCAA’s can also be handy here as they are very high in leucine, which is essential for triggering muscle growth. It should also have a good dose of high glycemic index (GI) carbohydrates. Carbohydrates top up your muscle glycogen stores (energy for next round of exercise) as well as help to get more of that muscle repairing and developing protein into the muscles where it is needed. Why high GI? Isn’t that bad? The glycemic index is simply a measure of how quickly the food causes a spike in blood glucose compared to pure glucose, pure glucose having a GI of 100. In this case we want those blood sugars to be elevated quickly because that means the sugar is going to be getting to our muscles quickly. So basically any carbohydrate sources which are easy to digest and absorb by your body.

  • Protein shake made with your choice of protein powder and drinking chocolate (most protein powders are very low in carbs so you will need to add some – this is why I like to use a plain unflavoured protein powder, so I can add my own flavours and carbs and so I can avoid Stevia and it’s derivatives because I think they taste vial)
  • White bread sandwich with nutbutter
  • White bread sandwich with marmite and cheese (Yes, I’m a kiwi so I like Marmite and the salty hit after training is GOOOOD)
  • A green smoothie made with yoghurt and a tablespoon of nut butter
  • Yoghurt with museli and some chopped fruit or berries
  • Protein balls
  • Your imagination is your limit, but make sure it’s either easy to prepare and take with you (won’t go off in a hot car during a 5 hour bike ride) or quick to prepare as you run in the door

Do I have to eat after every workout? No. Easy recovery workouts are just that – recovery  – and therefore should not be stressing your body beyond what it is currently capable of. Ergo no need for repair and adaptation to occur.  Any workout that leaves you tired or sore however, no matter how long or short it is requires you to target that nutrition to the places it is needed.

And while we are on the topic of times when you absolutely should eat something, before early morning training is one of those times. As endurance athletes it’s easy to buy into the messages suggesting various forms of ‘fasted’ training help you to tap into the ample supply of energy you have stored in your body fat. However, missing in these arguments is the important message that fat is actually really hard to burn – try putting a lump of fat and a lump of bread separated in the oven and crank the heat up and see which one catches fire first. The reality is, we have to put more energy in to get the fat into a form so that it can then be used to provide energy than we do for carbohydrates. So if you haven’t eaten all night, and bear in mind that during sleep is when your body does most of it’s repairing and recovery (read high energy expenditure), your quick access energy tank (carbohydrates stored in the liver) are pretty depleted. If you then try to train, your body is less likely to want to waste some of its limited carbs to generate energy to liberate fats for burning and is more likely to try to shut you down instead and get you to stop wasting what little carbs are left. The body in all it’s magnificence has one goal in mind: to keep you alive. Training on low energy is perceived by the body as a life threatening stress, so it isn’t going to respond the way we want it to and do what we think is logical. Unfortunately females, this is even more true for you than it is for the males because of differences in hormones.

 

Sometimes – Somethings gotta give.

After four weeks of running all over the city for various scans and follow-up appointments I now have the diagnosis and prognosis. Officially medial tibial stress syndrome grade 2-3, another 2 weeks off before I can begin the slow trot back to running. And while I’ve been kept busy with a new job, I’ve also had plenty of time to think in the mornings and evenings when I’d normally be out training but instead sit at home twiddling my thumbs.

leggie leg leg

I once had a friend tell me that I needed to sit back and acknowledge what a huge achievement my PhD was because we often lose sight of that when we spend our days surrounded by likeminded individuals striving towards the same goal. And in no place is this fact truer than in triathlon. Triathlon is an all-consuming sport. Even when training for the shorter distances, so not trying to squeeze in 6 hour cycles and 3 hour runs, we are training to be awesome at THREE sports. And it is very easy to lose sight of that when you are surrounded by equally nutty individuals.

It’s all come back to bite me recently. I’m very good at the ostrich approach, thinking that I’m coping fine until suddenly I’m not. And if I’m brutally honest, I knew that something wasn’t right for a while. But being my stubborn self with an ounce of super hero syndrome I tried to press on. Life had become stressful and I was struggling to fit it all in. Getting up early to train was hard, training wasn’t as enjoyable as it should have been, and while I enjoyed it once I got out there, it was an exhausting mental battle to get out the door. This shouldn’t be the case with a HOBBY. I don’t do triathlon to add more on my plate. It is my escape. Yet I had lost sight of that. I convinced myself that I could manage it all if I just dropped the training volume a bit. But to be honest this just added to the mental anguish because I knew I now wasn’t training to my full potential. Add a bit of financial stress into the mix and suddenly diet isn’t perfect either.

So with buckets of cortisol coursing through my system, less than ideal nutrition and an ever mounting fatigue that I couldn’t get on top of, something was going to have to give to make me wake up and realise I needed to stop.

As a sports biomechanist, with a focus on overuse injuries, I will be the first to argue that stress fractures are not as simple as too much training. You can get away with high training volumes, rapid increase or a slightly funky gait if that’s all your body has to deal with. But add life into the mix and it can become more than your finely tuned system can cope with. I’ve talked to another athlete who was recently pulled up short with a stress fracture and she also admitted to life events playing a part.

Triathlete’s are generally from a similar personality mould. The one that always ends up in a high stress life. Who piles task on top of task and wants to believe they are superman. And it is oh so hard to admit that we are not. That actually we need a break from something. Unfortunately, taking a break from life is very rarely an option.

My body has finally forced me to take a break, and it’s becoming clearer just how necessary it was. My crazy heart beats which are usually my indicator that I’m treading perilously close to the overtraining boundary has still not calmed down six weeks post A race. I am generally strict about 4 weeks of nothing post an Ironman race but by then I am itching to get back. While getting on my bike brings a smile to my face, I am in fact not ready to get back into the stupidly early mornings and the hours of listening to myself think.

It’s so important for us to realise that we are, still just human and that if we aren’t giving our bodies the chance to recover, with sleep, calm and good food, something IS going to BREAK. So make sure you schedule in some you time, somewhere in that hectic schedule. Take time out with your family. Have a good meal and a good sleep. Because if it’s not an injury, it could so easily be something more final like a heart attack.

 

The Importance of Your Bike Fit!

I have seen it mentioned a number of times lately that as triathletes, we are not cyclists. I would argue that we can learn a number of things from cyclists and cyclist related research. I couldn’t agree more, however when it comes to bicycle fit. Recent research has shown that triathletes have a different position on the bike compared to cyclists.[1] The research looked at joint angles (e.g. ankle, knee and hip angles) of triathletes on time-trial bikes compared to cyclists on road bikes and so we would expect some differences. I would argue however, that for the purpose of injury prevention, triathletes set-ups need to be different regardless of whether they are riding a time-trial bike, a road bike or a converted road bike with clip-on aerobars.

In the early days of triathlon, the sport was promoted as having a lower injury risk due to the cross-training effects of training for three sports rather than just one. The idea of cross-training is that the heart rate can be elevated with the associated cardiovascular benefits, however the muscles, bones, tendons and cartilage that have been getting a pounding during regular training get a break.

For endurance athletes, ‘overuse’ injuries are the most common and also the most frustrating, tending to resurface again and again regardless of how thorough the rehabilitation plan. But why is it that some athletes seem to breeze through hours of intense training without anything worse than a little DOMS (delayed onset muscle soreness) while others seem to suffer from the injury curse?

I believe it all comes down to balance. Balancing the work that the different muscles are required to do and the strength of all the muscles too. Some people are naturally gifted with perfect biomechanics, however even these people can develop overuse injuries should they neglect balance. For those of us ‘blessed’ with unusual joint shapes, lax ligaments and quirky gaits, developing a balance that supports these unique traits is even more important (and perhaps luckily, more obvious). We can achieve great things against great odds, as long as we understand our limitations and work with them.

Cycling TGA

So how does your bike set-up come in to all of this? Many people when asked to identify the cause of an injury will report it to be running related. Don’t get me wrong, running is often the movement that leads to the pain and is most disrupted by an injury. Often these individuals have tried all the running related rehabilitation options with limited success. They have also kept up swimming and cycling where possible as we all try to do. No matter what distance you are training for, right up to ironman and for a few beyond, the amount of time we spend on our bikes far outweighs the time we spend in the pool or on the pavements and trails. The number of muscle contractions occuring over a week of training for cycling trumps both swimming and running.

In research, running gets the injury focus because the load (impact and tissue stress) put through the body can reach up to 6-8 times our body weight. Cycling on the other hands sits at a respectable 1-2 times and so it is pretty safe to assume that cycling is not going to load the tissues of the body beyond their physiological limits. I do not dispute that the loads of running are more likely to result in injury, what I would argue is that the way an athlete moves and their ability to accommodate the loads of running can be influenced by their cycling.

Over the past four years I have researched Achilles tendon injuries in triathletes. The research focus was the mechanics of running but when determining the reasons behind the different movement patterns observed, I kept coming back to muscle strength and muscle balance. Many of you will be familiar with rehabilitation exercises that require 10 repetitions and 3 sets a day. If large numbers of relatively minor muscle contractions over the course of a few weeks are able to improve muscle balance, then just think how great an influence cycling has on muscle balance.

Which brings me back to triathletes are not cyclists. Purely because cyclists do not also have to run long distances, and so it is important that the bike set-up reflects this. It is important to try and keep the legs a bit fresher for the run. It is equally important to ensure that we don’t over-strengthen muscles at the expense of some of the important running muslces. Over-strengthening can create imbalances.  Imbalances can stress the tissues of our bodies beyond breaking point and start the chronic injury cycle. Maintaining the balance of muscular strength for both running and cycling is as important if not more than the balance between maximum speed and power on the bike and maintaining fresher legs for running.

A good bike set-up is paramount to maximising your triathlon experience. Done by someone who understands the differing demands of triathlon and the specific distance you are training for. And possibly even more important, a bike fit which is specific to YOU and all your strengths, weaknesses and quirky bits.

  1. Bini RR, Hume PA, Croft J. Cyclists and triathletes have different body positions on the bicycle. European Journal of Sport Science 2012;14(sup1):S109-S15