With holiday season here and the heat wave that we’ve all been treated to here in the UK, working out outside can become a little more difficult. While we complain the Winters are too cold and dark to take our workouts outdoors, this Summer is proving that training in the heat isn’t so easy either. So, we’ve addressed some of the most common questions for when it comes to training in the heat to help you maximise your workout outdoors this Summer.
How Long Does It Take To Acclimatise To The Heat?
Like anything in fitness, when it comes to training in the heat and in differing humidity, everyone is different. Generally, it can take around 7 to 10 days of structured training for the body to slowly adapt to different heat levels. During this time you should be aiming to work out for around 45 minutes to 1 hour per session. However, the time it takes to acclimatise to heat can also depend on several other factors including individual hydration and fitness levels. Be sure to stay hydrated during hot conditions and replenish your electrolytes after each session for the best recovery.
What Percentage Of Your Regular Performance Should You Aim To Reach?
Our training performance is based on physiological factors such as heart rate and our individual VO2 max oxygen uptake (how much oxygen you take in during maximum exertion). VO2 max is a measure of how intense exercise is and also a measure for endurance, as your vo2 max increases so does your heart rate. Factors that affect performance include altitude from air pressure and temperature. When training in the heat, it’s 100% normal not to be able to reach that PB or top speed and performance often decreases due to the body adjusting.
What Affect Does Heat Have On The Body When Training?
Heat acts as an additional stressor when training which results in cardiovascular adjustments. Some of these include changes in blood flow, increased sweating, an increase in your heart rate and a lower oxygen uptake. When we are exposed to hot conditions the body will try and cool itself down and regulate temperature through increased sweating, which in turn increases blood flow to the skin’s surface. This means we lose blood flow to the muscles and vital organs during training as well as losing water and electrolytes through sweat.
Because blood flow to the muscles and vital organs is decreased in the heat, the amount of blood pumped from the heart is also decreased and to compensate for this adaptation the heart works harder. This is why heart-rate can increase more quickly despite the workout being less intense!
Not only that but if you are looking to take part in some endurance training, hotter conditions can also alter the way the body creates and burns energy. In order to train at high intensities for longer periods of time the body relies on several sources of fuel, including both fats and carbohydrates. To burn fat as energy, the body needs oxygen, whereas carbohydrate energy stores are an anaerobic source of fuel and don’t require oxygen. When hot conditions cause the blood flow to the heart and muscles to decrease it also decreases the amount of oxygen that is delivered to the muscles and as a result the body is forced to rely on carbohydrates as fuel. However, our carbohydrate stores in the body are limited, therefore you may find in the heat the body will reach exhaustion sooner than usual.
So, How Will My Performance Differ?
The percentage to which you can train in the warm weather can vary again depending on the temperature increase itself and other factors such as altitude and humidity. Not only that, but dehydration can often come into play when training in the heat to further the disproportional intensity effect that you’ll see. So don’t be disheartened! Not being able to hit your PB and max speed is totally normal until the body adapts and even then you need to pay close attention to hydration and replenishing electrolytes.
What Should I Eat and Drink Before, During And After Training In The Heat?
Nutrition pre, intra and post-workout is important regardless of the training conditions but when it comes to staying safe in hot conditions pay close attention to losing salts and water.
Before training be sure to keep hydrated during the day, or if training early in the morning make sure you have consumed enough water (around 600ml) two hours prior to working out when possible. If you need a caffeine fix in the morning, taking a pre-workout supplement is a great option. Sadly coffee can actually decrease blood flow and dehydrate the body so definitely stick to water or pre-workout supplements over your usual cup!