This week's heatwave has led to plenty of discussion amongst runners.

Should I slow down?

Should I skip intervals?

Should I avoid running altogether?

The answer will depend on your individual circumstances, but for most healthy runners, there is actually a valuable opportunity hidden within summer training.

Heat Adds an Extra Training Stimulus

When we run in hot conditions, our bodies aren't just adapting to the running itself.

They're also adapting to the additional challenge of regulating body temperature.

In many ways, your body treats a hot run as a bigger training stimulus than the exact same run completed on a cool spring morning.

That doesn't mean every run needs to be hard.

It simply means the heat adds another layer of demand, and if we manage that demand sensibly, the body can adapt.

Your Blood Volume Can Increase

One of the recognised adaptations to repeated heat exposure is an increase in plasma volume — the liquid part of the blood.

Put simply, this can allow your cardiovascular system to work more efficiently.

It can help your heart pump blood around the body, support oxygen delivery to working muscles, and help transport heat away from the body's core.

Over time, runners who train consistently and sensibly in warm conditions may find their heart rate becomes lower at the same pace or effort than it was when the heat first arrived.

Your Body Gets Better at Cooling Itself

Your body can also become better at cooling itself.

With repeated exposure, you may begin sweating earlier, regulate temperature more effectively, and feel less overwhelmed by the sensation of running in warm conditions.

Your core temperature may rise more slowly, and the same warm-weather run that felt very uncomfortable at first can start to feel more manageable after a period of sensible exposure.

This is one of the key reasons we don't want to treat every hot day as a reason to stop training completely.

The Benefits Can Carry Into Cooler Weather

When we run in hot conditions, our bodies aren't just adapting to the running itself. They're also adapting to the additional challenge of regulating body temperature.

In many ways, your body treats a hot run as a bigger training stimulus than the exact same run completed on a cool spring morning.

Heat Adds an Extra Training Stimulus

Perhaps the most interesting thing about heat adaptation is that some of these benefits don't disappear when the weather cools down.

The increase in plasma volume can improve endurance performance, cardiovascular efficiency and recovery.

This is one reason why elite athletes sometimes use heat training as an alternative to altitude training.

The Goal Is Not to Suffer

This does not mean every run should become a sufferfest.

In fact, trying to maintain your normal pace during a heatwave is often the wrong approach.

The goal isn't to prove how tough you are.

The goal is to keep training safely.

That might mean running slower than normal, taking extra recovery between efforts, carrying water, choosing shaded routes, reducing intensity, or stopping early if you feel unwell.

At Cheltenham Running Club, we've adjusted sessions this week to reflect exactly that.

The focus is on consistency, community and sensible training rather than chasing personal bests in 30-degree temperatures.

Some Benefits May Carry Into Cooler Weather

The strongest and clearest benefit of heat adaptation is that your body becomes better at coping with warm conditions.

But some of those adaptations may also help when the weather cools down, especially if they allow you to keep training consistently through the summer.

The important point is this: if you stop running every time it gets warm, you don't get the fitness benefits of those missed runs.

You don't get the aerobic development.

You don't get the strength and resilience from consistent training.

You don't get the confidence of knowing you can adapt when conditions are less than perfect.

So while heat training is not magic, and it does not guarantee faster autumn race times on its own, training safely through the summer can help you maintain momentum when others may lose it.

It Is Only Late June

It's also worth remembering that we're only in late June.

There is likely to be plenty more warm-weather running still to come this summer.

July and August often bring additional hot spells, and runners who completely avoid training whenever temperatures rise can find themselves starting from scratch every time the next heatwave arrives.

The runners who gradually and safely expose themselves to warmer conditions throughout the summer often cope far better when those hotter days return.

That doesn't mean running hard in dangerous conditions.

It means being sensible, adjusting the session, slowing the pace, hydrating properly, and learning how your body responds.

Summer Training Builds Autumn Results

Many of the club's biggest target events take place in September, October and November, when temperatures are usually cooler and conditions are often more favourable for faster running.

Run Cheltenham.

The Cirencester Half Marathon.

Cross-country races.

Cardiff Half Marathon.

These are the events where many runners are hoping to achieve personal bests and breakthrough performances.

But the work that supports those performances isn't built in a single week of perfect weather.

It's built through months of consistent training.

Safe Summer Running Could Be a Huge Unlock

If you're hoping for strong autumn race results, training safely and consistently through the summer could be a huge unlock.

Not because every hot run needs to be fast.

Not because suffering through the heat automatically makes you fitter.

But because smart summer training helps you keep building fitness, confidence and resilience while your body gradually becomes better at handling warm conditions.

So if this week's runs feel a little slower than usual, don't worry.

You're not losing fitness.

You may well be building the foundations for your strongest racing season yet.