It’s finally that time of year again. When we can head outside without the need for woolly jackets and long pants. We can lace up simply with shorts and a top and run until our hearts are content. But though this is a joyous occasion for many runners, it also brings about dangers of excessive sun exposure, which can lead to numerous medical problems, specifically hydration issues.
Let’s face it, our body needs water. Without it, our blood plasma levels decrease, causing our blood to thicken, which adds extra stress on our heart to pump it around the body. We not only lose water through sweat, but also through our breath, thus the harder we exercise, the more water we are losing with the harder breathing. (Noakes, 2006)
So if you’re unsure on how to beat the heat and stay hydrated through the coming months, here are our top tips for you to follow.
Know Your Numbers
The key to making sure you stay hydrated is knowing your numbers in terms of sweat rates. If you know how much you sweat (usually represented as a value of Litres per hour), then you can plan how much liquid you need to ingest. The great part is, working out your sweat rate doesn’t require fancy laboratories with mind-boggling tools, all you need is a simple set of scales.
Prior to your run, weigh yourself while naked to assess your pre-run mass. If you plan on drinking water or a special electrolyte drink, try and weigh yourself while holding the bottle/s. Once you finish your run, once again weigh yourself naked and holding the bottle/s, which will be your post-run mass.
To work out your sweat rate value, subtract your post-run mass from your pre-run mass, and divide this by the time you exercised for.
Eg. Pre-run mass:70.5kg / Post-run mass: 69.3kg / Exercise time: 1hour
(70.5 – 69.3) ÷ 1 = 1.2kg/hour
Now we know that mass and volume are linked, thus 1kg has the same mass as 1L. So for this example above, their sweat rate is 1.2L/hour of exercise.
Using these methods above, you can work out your own sweat rate, and plan around this for your next run or exercise session. If you’re unable to take in liquids during your run, then it is essential that post run you replenish those lost fluids.
Pre-Hydrate
To get ahead of the game, try and hydrate with fluids prior to your run. And by this we don’t mean guzzle a litre of water 15 minutes before heading out. Pre-hydrating means ingesting fluids in the hours leading up to your run. By doing this, you are increasing the blood plasma levels, making your blood easily accessible for nutrients and not placing extra stress on your heart to pump the blood through the body. By pre-hydrating, you’re also making sure that your muscles are engorged with fluids, and can begin exercising at optimum states.
Pre-Cooling
Evidence is emerging about a strategy called pre-cooling, which is said to increase performance in hot conditions. Pre-cooling involves wearing a cooling vest, or something as simple as placing your hands in icy water, which cools the body’s core temperature, thus reducing the heat stress placed on organs. A study out of Bharathiar University in India and Vrije University in Netherlands found that aerobic exercise performance vastly improved after a protocol of using a cooling shirt. (Bogerd, Perret, Bogerd, Rossi, & Daanen, 2010; Rajeswaran, Shivaji, & Jeyavelmurugan, 2011)
Functional Clothing
Many of us head out for a jog in an old shirt that we received after competing in the Joe Blogs fun run five years ago, but is it really helping you stay cool during a hot, summer run? Probably not. A lot of clothing companies have their own claims about how their materials wick sweat away and keep you cooler, which we’re sure some of them live up to their claims. But many are just marketing spin and don’t do much more than your five-year-old fun run shirt. Aim to buy clothing from a reputable clothing manufacturer that actually has proof of their materials working. You’d be surprised at how much difference a technical fabric can make to your running performance. Check out the new range by On Running which has options of Clima-shirts, Performance shirts, and hybrid pants which are ideal for running in the heat.
There are many, many more heat-busting strategies out there. This is just a small list. If you’re after any more tips and tools you can use to beat the heat this summer, let us know through our Facebook page.Bogerd, N., Perret, C., Bogerd, C. P., Rossi, R. M., & Daanen, H. A. M. (2010). The effect of pre-cooling intensity on cooling efficiency and exercise performance. Journal of Sports Sciences, 28(7), 771-779.
By Liam Bromilow.
Sources:
Noakes, T. D. (2006). Exercise in the heat: Old ideas, new dogmas. International SportMed Journal, 7(1), 58-74.
Rajeswaran, S. T. N., Shivaji, G., & Jeyavelmurugan, G. (2011). Effect of pre-cooling and warm-up on aerobic endurance performance. Journal of Physical Education & Sport, 11(44), 461-464.
