One of the things I love about fitness is understanding what exercise is actually doing inside our bodies.
We often think about exercise in terms of losing weight, getting stronger or changing the way we look. But some of the most important benefits are happening where we can’t see them.
One of those benefits is the way exercise can improve insulin sensitivity and blood-sugar control.
So what does insulin actually do?
When we eat carbohydrates, our digestive system breaks them down into glucose. That glucose enters the bloodstream and provides an important source of energy for our bodies.
Insulin is a hormone produced by the pancreas. I like to think of insulin as a key.
It helps unlock the door to our cells so glucose can move out of the bloodstream and into the cells, including our muscles, where it can be used for energy or stored for later.
And this is where exercise gets really interesting
When we exercise, our muscles suddenly need more energy.
Working muscles increase their uptake of glucose from the bloodstream. Muscle contractions can stimulate glucose uptake through mechanisms that don’t depend entirely on insulin.
I think that’s pretty amazing.
And the benefits don’t disappear the moment we finish exercising. After a workout, our muscles can become more sensitive to insulin, meaning insulin can do its job more effectively.
In very simple terms, the insulin “key” works better.
Another reason I love strength training
Resistance training has another important benefit: building and maintaining muscle.
Muscle isn’t just about looking toned or being able to lift something heavy. It’s metabolically active tissue and an important site for glucose use and storage.
Maintaining our muscle becomes particularly important as we get older, when we naturally tend to lose muscle unless we actively challenge it.
That’s one of the reasons I’m so passionate about encouraging people to include some form of resistance training in their lives.
And you don’t have to become a bodybuilder!
Weights, resistance machines, bands and body-weight exercises can all be useful. The important thing is finding something appropriate for you and gradually progressing.
Cardio counts too
It isn’t only weight training that helps.
Walking, cycling, swimming and other forms of aerobic exercise can all improve insulin sensitivity and support blood-sugar management.
And this is something I really want people to understand:
Exercise doesn’t have to be extreme to be worthwhile.
A walk counts. A cycle ride counts. A yoga class counts as movement, although it may not provide the same aerobic or strength stimulus as dedicated cardio or resistance training. A gym session counts.
It all adds up.
My simple way of remembering it
EXERCISE → muscles use glucose → muscles become more responsive to insulin → better blood-sugar control.
For me, this is another reminder that exercise is about so much more than weight.
We’re training our muscles, heart and lungs, but we’re also influencing what is happening metabolically inside the body.
That’s why I encourage people to think less about exercising simply to “burn calories” and more about building a body that works well.
Move because you want to be stronger.
Move because you want more energy.
Move because you want to protect your health as you get older.
And, most importantly, find movement you actually enjoy — because the exercise that makes the biggest difference is usually the exercise you can keep doing.
Selena Hilltout
Personal Trainer • Yoga Teacher • Mindset Coach
