Devlin Brown at the water cooler: How to stay cool during training
Try a combination of strategies before, during and after exercise to beat the summer heat
Q: Last week you explained that heightened sweating may be a sign of increased fitness. I take my fitness seriously, but lately my perspiration is just not enough to deal with the Joburg heat. What can I do to stay cool during my training?
A: To stay cool during training, don’t curl in the squat rack, don’t text while hogging a bench, and wipe down your piece of equipment after using it. Don’t run or cycle two or more abreast on the road and if you want to take your sausage dog to the park run, don’t.
Most importantly, despite it being a viral video, it is not cool to wys jou vleis.
However, if you are referring to keeping your core body temperature down then you are in luck: there are a few tricks you can learn from competitive athletes.
David Leith, a high-performance biokineticist at the Sports Science Institute told Business Day during our recent feature on altitude training that hot and humid conditions are known to impair exercise performance because of the increased demand on the cardiovascular, thermoregulatory and metabolic systems, as well as increased thermal strain and perception of effort.
Exercise in the heat disrupts the body’s core temperature homeostasis and triggers the thermoregulatory system to oppose the disruption. “Specifically, sensors in your central nervous system stimulate the hypothalamus in the brain to relay to various organs and systems in your body to resist the change in core temperature,” he says. One of those is sweating.
During high-intensity exercise in the heat, there is an increased demand for blood flow from the working muscles and from the skin, causing greater vasoconstriction (narrowing of veins) at the internal organs to direct more blood flow to these areas. “However, since a certain central blood volume needs to be maintained for normal physiological processes to continue, cardiac output becomes insufficient to meet these demands, meaning either blood supply to the muscles will become insufficient or core temperature will increase.”
Leith says that research suggests that the latter typically happens, causing the “central governor” in the brain to trigger physiological responses that reduce exercise intensity and thus protect the body from catastrophe.
“For athletes needing to exercise at their full capacity during hot Johannesburg summers, for instance, they can consider four strategies to help prevent or delay a performance-limiting increase in core temperature and maintain performance capacity,” says Leith. These are strategic training timing, heat acclimation, hydration and cooling strategies.
If you can help it, don’t be stupid and run in the midday sun. Time your high-intensity sessions to take place early in the morning or do it indoors in an air-conditioned gym
Strategic training timing is a fancy way of saying, don’t be stupid and run in the midday sun. Time your high-intensity sessions, so that your body will be working hardest early in the morning or do it indoors in an air-conditioned gym.
Heat acclimation involves planning specific sessions in the heat to promote physiological adaptations “that will reduce physiological strain or heat stress when exposed to the heat during an event”. Coaches have developed effective ways of achieving this adaptation.
Hydration means drinking water. “Increased core temperatures induce an increase in an athlete’s sweat rate to facilitate evaporative cooling. This may lead to dehydration and associated thermoregulatory and cardiovascular strain,” says Leith. It is widely accepted that our brain, or central governor as sports science folk like to call it, is clever and so drinking to thirst is a smart way to ensure you are sufficiently hydrated.
There are specific recommendations of the number of millilitres of fluid to be consumed per kilogram of body weight (and how many hours before the start of a big event), in relation to your sweat rate of litres per hour, including the targeted gram to litre of sodium to mix into the solution to prevent muscle cramping. For this, visit an expert because The Water Cooler doesn’t dispense bro science.
For cooling, there are pre, per (during) and post-exercise strategies. For performance, pre and per are important and research suggests measurable improvement in performance when you are able to cool your core temperature. “Ultimately combining pre- and per-cooling confers a cumulative beneficial effect on performance greater than either used in isolation,” says Leith.
He says there are various strategies such as ice towels and vests, but ultimately the best intervention for both pre and per-exercise cooling is to ingest an ice-slurry mix.
There you have it. For all the science in the world, the best way to stay cool and perform at your best is to enjoy a slush puppy! Except, ditch the corn syrup, monopropylene glycol and sodium benzoate, and stick to good old-fashioned H2O.