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The Dangers Of Excessive Exercise

Now, it’s no secret that exercise is great for your health. From increased fitness levels to various mental health and stress benefits, you can never have too much of a good thing, right? Wrong. Exercising excessively forces our bodies to deal with continuous levels of stress, which can be harmful and cause long term health problems, as well as mental issues.

Having suffered a phase of excessive exercising and battling with Amenorrhea, Grenade® athlete and fitness coach Hayley Madigan knows how dangerous it can be putting excessive strain and stress on your body in order to reach somewhat unattainable goals.

We caught up with Hayley to find out more about her fitness journey and how she’s learned that exercise is all about balance.

“Exercising can be a positive release for most of us. Be it a stress reliver or a feel-good endorphin rush, exercise has outstanding benefits both mentally and physically. But what happens to our bodies when we exercise excessively? Can we cope with the continuous stress that is forced upon our bodies or does something have to be sacrificed in order to keep our bodies going?

Surprisingly, not just for women but for men also, excessive exercising can lead to a complete shut-down of the reproductive system. It is more obvious in women than it is in men but, for both genders, this can be a dangerous consequence of over training and over restriction. Women tend to lose their menstrual cycles and enter a Hypothalamic Amenorrhea state (absence of periods) whilst men’s testosterone levels can severely drop which is equally detrimental.


So, for me personally, I unfortunately lost my periods for over three years. My training was excessive, and I restricted my food intake because my goal was extreme fat loss continuously due to competing in Bikini competitions.

Competing within natural federations, and as a natural athlete, meant that I had to force my body into an unnatural state for a female.  I had to reach low levels of body fat whilst maintaining as much muscle mass as possible and this required me to train a minimum of once a day every day with some two-a-day sessions thrown in mid-week. Whilst my exercise was excessive, my diet was very low in calories and nowhere near enough for my body to function properly in order to attain the low body fat levels that were required for competition level.  Hence, my body shut down any unnecessary systems in order to function and that included my reproductive system.

The dangers of excessive excercise


Now, the consequences of a female’s menstrual cycle stopping is quite dramatic. Not only does this weaken our bones due to a lowered bone mineral density by the absence of oestrogen, it also decreases our resting metabolic rate quite strikingly – it was been claimed that if a female is in a Hypothalamic Amenorrhea state she burns 15% less calories a day (this equates to 337 calories less a day in a 150lb female with a TDEE of 2,250 calories*) which makes it even harder to reach lower body fat levels once this state is reached therefore adding more stress to the body by a furthered over restriction. With the combination of lowered reproductive hormones, increased anxiety, depression and mood swings, the risk of infertility is also high, and this can put a lot of stress mentally upon females, especially if they are wanting to start a family.


I’ve highlighted just a few of the reasons why excessive exercise can lead to complications but the type of exercise you’re doing also has an impact on how your body is going to respond to the added stress. High-intensity interval training, also known as HIIT, has become increasingly popular over the last few years and is one of the main training methods that increases cortisol (stress hormone) vastly in the body. Your body will see this type of training as a stress and therefore has to adapt to suit the stress upon it. Yes, it’s brilliant for increased fitness levels and great for burning calories too, but not so great for females to do repeatedly week in week out. HIIT has been shown to over-stress the body so much that just HIIT alone can be enough to cause the onset of Amenorrhea. It is recommended that 2-3 HIIT sessions per week are an absolute maximum for females.

Now, by all means, this doesn’t mean you need to stop exercising or stop doing the HIIT sessions that you love, far from it, I train a minimum of 8 x a week, sometimes even 10 x a week and I have regained my menstrual cycle to a perfect 28-day reoccurring cycle and have had it consistently for the last 11 months.


I introduced rest days! I actually started to allow my body the rest it needed to in order to recover from the excessive exercise. I increased my calorie intake to match my calorie output and I started to exercise smarter by reducing the amount of HIIT sessions I did. I also adapted my cardio sessions by increasing my daily step count as opposed to slaving away on the stair master. The combination of all of this allowed the stress that was harming my body to be vastly reduced thus enabling my body to regain its natural rhythm and have a consistent monthly cycle.

To ensure you don’t face the dangers of excessive exercising, make sure you have a healthy balance in your life with training, rest days and taking time out to focus on just you. Allow yourself a healthy relationship with both exercise and food - this will enable your body to fuel correctly for the exercise you want it to undertake. Eat all food groups and make sure adequate protein intake is high enough to reach those gains!"

For more tips and advice on how to maintain a balanced relationship with exercise, head over to Hayley’s Instagram where she posts regular workouts and informative posts on her experience. If you’re after more training tips and tricks, you can always visit our blog – find out 7 easy ways you can up your step count today!

*(L. McDonald The Women’s Book: Vol 1. 2017)