Running in the heat: mistakes to avoid

Running in hot weather can quickly turn a normal session into a much more demanding effort.

The body then has to manage both the physical effort and the regulation of body temperature, which greatly increases physiological fatigue.

Without adaptation, certain mistakes can lead to dehydration, heat stroke, decreased performance, or more difficult recovery.

Adapting your training during hot periods doesn't mean stopping running completely, but rather learning to better manage the constraints related to the heat.

Why running becomes more difficult in the heat

When the temperature rises, the body has to exert more effort to maintain a stable internal temperature.

To dissipate heat, the body particularly increases:

• Sweating
• Blood flow to the skin
• Heart rate

Result: the same session often feels much more difficult than at moderate temperatures. The perceived effort also increases more quickly.

 

Mistake #1: keeping the same pace as usual

One of the most common mistakes is to want to maintain exactly the same performance despite the heat.

However, when temperatures rise, physical capacities naturally decrease.

Continuing to run at the same intensities can:

• Greatly increase fatigue
• Accelerate dehydration
• Cause heart rate to rise excessively
• Make recovery more difficult

Adapting your pace and accepting to slow down often remains the smartest strategy.

 

Mistake #2: neglecting hydration

With the heat, fluid loss greatly increases due to sweating.

Even slight dehydration can quickly affect:

• Performance
• Concentration
• Recovery
• Perception of effort

Waiting until you're thirsty to drink is not always enough in hot weather.

Regular hydration throughout the day is generally more effective than a very large intake of water just before exercise.

 

Mistake #3: running during the hottest hours

Running in the middle of the afternoon during a heatwave greatly increases thermal stress.

The most suitable times are often:

• Early morning
• In the evening
• In shaded areas

Limiting direct sun exposure generally helps to tolerate the effort better.

 

Mistake #4: wearing unsuitable clothing

Equipment plays an important role in heat management.

Clothing that is too thick or not breathable complicates heat dissipation.

In hot weather, it is generally preferable to opt for:

• Breathable fabrics
• Lightweight clothing
• Light colors
• A cap or sunglasses if needed

Thermal comfort can greatly influence the perceived effort during the session.

 

Mistake #5: underestimating the signs of overheating

The body often sends several signals before a real heat stroke.

Symptoms to watch out for include:

• Dizziness
• Nausea
• Headaches
• Unusual chills
• Extreme weakness
• Confusion

Ignoring these signals and continuing to run can become dangerous. If in doubt, it is best to slow down, stop, and cool down quickly.

 

Mistake #6: neglecting electrolytes

Sweating does not only cause water loss.

It also leads to a loss of minerals such as:

• Sodium
• Potassium
• Magnesium

During long runs or in hot weather, these losses can affect:

• Recovery
• Cramps
• Fatigue
• Fluid balance

Diet and certain adapted drinks can help compensate for these losses.

 

Mistake #7: wanting to maintain your usual volume at all costs

The body is already under additional stress from the heat.

Trying to maintain exactly the same training volume can sometimes lead to:

• Excessive accumulation of fatigue
• Decreased recovery
• Increased risk of injury

Temporarily adapting:

• Volume
• Intensity
• Duration of outings

often allows for better management during very hot periods.

 

How to recover better after a run in hot weather

Recovery becomes particularly important after exercise in high temperatures.

A few simple habits can help:

• Drink regularly after the session
• Gradually cool the body
• Eat enough
• Prioritize quality sleep

Heat generally increases overall fatigue, even during moderate sessions.

 

What to remember

Running in hot weather primarily requires more adaptation and listening to your body.

The main mistakes often involve:

• Poor hydration
• Too high intensity
• Lack of adaptation to climatic conditions

Slightly slowing down, better managing recovery, and adapting your habits generally allows you to continue running more serenely during periods of high heat.