Exercising Safely in the Heat

Our bodies are very good at trying to keep a regular body temperature. We have a few ways to naturally control and regulate heat between our body and the environment around us. When heat and humidity increase during the summer months, exercising in the heat can make the task of regulating your body’s temperature tougher.

Christine Blonski, DO, is a board-certified primary care sports medicine primary care physician at Rochester Regional Health Orthopedics – Culver who also serves as the head team physician for RIT Athletics and program director for primary care sports medicine fellowship at Rochester Regional Health.

Dr. Blonski explains how your body naturally regulates its temperature, the most effective ways to keep your body functioning well in high temperatures, and how to prevent heat-related illnesses.

How your body keeps itself cool

The human body uses four basic methods to keep itself regulated with heat: conduction (releasing heat to cooler objects), convection (air flow), evaporation (sweat) and radiation (taking in the heat we get from the sun and releasing heat our body produces as we burn calories).

Keeping our internal temperature consistent is a balance between how much heat we take in from the environment around us and how much heat our bodies are producing. When we are exercising in higher temperatures, our bodies release even more heat. That heat production is what puts us at risk of heat illness when it’s hot outside.

You can prepare ahead of a warmer workout by giving your body what it needs in advance.

“Being aware of your body and…planning ahead is probably the smartest thing that you can do when you know that you're going to have to be in a hot environment for an extended period of time,” Dr. Blonski said.

What to do before and during exercise in hot weather

When you are getting ready to do a workout, practice a sport, play in a tournament, or other physical activity, think of what you might need to do to prepare your body ahead of time.

Gradual heat exposure: Don’t go all out during your first outdoor workout. Allow your body 10-14 days to adjust to the warmer temperatures with shorter, lighter workouts.

Hydrate ahead of time: Giving your body the extra fuel it will need in advance gives you a better opportunity at a good workout. Hydration lets your body store fuel for evaporative cooling.

“Hydrating continuously in a hot environment is an important mechanism for preventing heat illness,” Dr. Blonski said.

Dress light: Wear light-colored, lightweight clothing that’s loose-fitting. This allows for more air flow and UV protection against the sun.

Seek out shade: If you can stay in the shade during a practice, during a workout, or in between tournament games, that will help your body recover better.

Check your meds: Knowing your medical history is vital to exercising in hot temperatures. Some medications or supplements can affect how your body is able to adapt to temperature changes. Talk with your doctor about what you take so you can let that conversation inform how you prepare for the heat.

Keep track of time: Don’t let the workout go on too long. The longer your body is exerting itself, the more heat it is giving off and the harder you will need to work to regulate your internal body temperature. Take breaks if you need to.

Warning signs that you are overheating

Exercising in the heat can lead to significant fatigue and dehydration. Pay attention to how your body feels. If you notice any of the following symptoms, take a break and let your body cool down.

• Lack of sweating
• Cramping, muscle tightening
• Swelling in hands/feet
• Lightheadedness

You may be experiencing progressively worse symptoms of heat exhaustion or heat stroke if you have:

• Nausea/vomiting
• Agitation
• Confusion
• Irritability
• Seizures/loss of consciousness

If untreated, heat stroke may cause damage to your brain, heart, kidneys and muscles. 

“The longer you wait to take care of heat illness-related symptoms, the harder it is to reverse the consequences,” Dr. Blonski said. “When you’re noticing those early warning signs that you’re hot, pay attention to your body.”

When to avoid exercising in the heat

There are some situations where you should take a break for the day or find a cooler place to exercise, perhaps indoors.

Some people face a higher risk of developing heat exhaustion or heat stroke by exercising in hot weather, such as:

• Overweight/obese individuals
• Young children/seniors
• Parkinson’s patients
• Patients with uncontrolled diabetes
• Patients with alcoholism
• People recovering from GI or upper respiratory illnesses

“If you're just recovering from an illness, going full out and exercising in the heat at a tournament or something similar is not a smart option,” Dr. Blonski said. “Give your body the break that it needs to fully recover from that illness before you add this extra heat stress.”