High-Intensity Exercise Isn't the Enemy

It may just be my personal algorithm, but lately I've seen a lot of noise surrounding high-intensity exercise and women's health. Depending on who you listen to, high-intensity can supposedly send your cortisol levels through the roof, leave you feeling inflamed and puffy, or throw your hormones completely "out of balance."

But how much of this is actually supported by science?

Yes, exercise does indeed place stress on the body, but that's not inherently a bad thing. In fact, it's a necessary part of how we build strength, improve fitness, and adapt to greater physical challenges.

Exercise Is a Stressor, and That's the Point

When we exercise, especially at higher intensities, our heart rate increases, our bodies mobilize more energy, and hormones like cortisol and adrenaline rise to support that activity.

And that's exactly what's supposed to happen!

Cortisol gets a bad reputation, but it serves an important purpose. It helps make energy available so our muscles can keep working. Just because cortisol increases during a workout doesn't mean something is wrong or that we're somehow damaging our hormones.

With adequate recovery, our bodies adapt to training, allowing us to lift heavier, move faster, and sustain harder efforts.

Of course, there's a difference between challenging yourself during a tough workout and consistently pushing beyond what your body can reasonably handle.

Training for Sport Versus Training for Life

Competitive athletes often train at volumes and intensities that most people will never come close to. They're preparing for competition, pushing performance limits, and sometimes deliberately accumulating fatigue in the process.

But most of us aren't competing at the highest level. We're exercising to get stronger, improve our cardiovascular fitness, and stay healthy and physically capable as we age. And we can absolutely benefit from challenging ourselves without needing to train like professional athletes.

So when you see former high-level or competitive athletes blaming their previous approach for the problems they've experienced, and then trying to sell you something that looks awfully similar but has been repackaged as a healthier alternative, I think it's worth keeping this distinction in mind.

Their experiences may be completely legitimate, but that doesn't mean the same concerns automatically apply to someone doing CrossFit three or four times a week.

And let's not forget, high-intensity exercise doesn't mean going all out every single workout. Good programming accounts for different intensities, individual abilities, and recovery. There's a lot more to training than simply how hard you can push yourself!

When Training and Recovery Don't Match

That said, there are real concerns when training demands consistently exceed our ability to recover.

If you're constantly exhausted, your performance is declining, you're not sleeping well, or you keep getting injured, those are signs worth paying attention to. Sometimes that means reconsidering your training load, but we also need to talk about fueling.

One important example is Relative Energy Deficiency in Sport, or RED-S, a condition associated with problematic low energy availability. Essentially, this happens when there isn't enough energy left to support the body's physiological functions after accounting for exercise expenditure.

The consequences can be significant, including disruptions to reproductive hormones, menstrual function, bone health, and immune function. And you don't have to be an elite athlete or visibly underweight for this to happen.

Here's where I think the conversation sometimes goes wrong. RED-S isn't exclusive to high-intensity exercise. It can develop when food intake doesn't keep up with physical activity, whether because someone isn't eating enough, their training load is particularly high, or a combination of both.

Of course, training volume and intensity still count, and sometimes reducing your workload is necessary. But blaming high-intensity exercise alone overlooks an important part of the physiology.

Let's Stop Making Women Afraid to Train Hard

We need to be careful about how we talk about exercise, especially when those conversations leave women questioning whether pushing themselves in the gym is somehow harming their health.

High-intensity exercise has well-established benefits for cardiovascular health, insulin sensitivity, and physical fitness. And while excessive training, inadequate fueling, and insufficient recovery can have real consequences, those risks don't justify treating intensity itself as something harmful.

And frankly, I think we should be encouraging more women to discover what their bodies are capable of, rather than giving them another reason to be afraid of exercise.