Exercise is good for you. That is not in question here, and nothing below is an argument for stopping.
What is true at the same time is that training is a demand, and demand has to be paid for. When the amount you are doing outruns the amount you are eating, the menstrual cycle is one of the things that gets switched off.
It is the gap, not the sport
There is no number of hours that is safe or unsafe. The same training week is comfortable for someone eating enough and costly for someone who is not. This is why two people doing identical sessions can have completely different experiences.
It is also why the solution is rarely “stop exercising”. More often it is to narrow the gap from both ends: eat more, and ease the load somewhat while things settle.
RED-S
You may come across the term RED-S — Relative Energy Deficiency in Sport. It describes what happens across the whole body when energy availability stays low: effects on bone, immunity, mood, concentration, gut function and performance, as well as the menstrual cycle.
The performance part is worth sitting with, because it undercuts the usual trade-off. Under-fuelled training does not produce a leaner, faster athlete in the long run. It produces one who gets injured, sleeps badly and stops improving.
Rest days are training
A rest day with a “light” run in it is not a rest day. Recovery is when adaptation actually happens, and a week with no gaps in it is a week with no adaptation in it.
Sleep belongs in the same category. Short, broken sleep raises the demand on the body as surely as an extra session does.
What reducing load can look like
This is general information, and the specifics belong with a clinician or a sports dietitian who knows your history. Broadly, people are often guided towards:
- Taking one or two genuine rest days a week.
- Reducing the hardest sessions first, rather than trimming a little off everything.
- Keeping movement you enjoy, at an intensity that leaves you able to talk.
- Adding food rather than only subtracting training.
- Giving it months. Cycles rarely return in a fortnight.
If stopping feels impossible
If the idea of training less brings real anxiety, or if sessions feel compulsory rather than chosen, that is worth saying out loud to your GP. It is a common experience, it is understood, and it is treatable. It is also much easier to address early.
And if training is not the cause
Plenty of people with absent periods are not over-training at all. PCOS, thyroid conditions, raised prolactin and premature ovarian insufficiency have nothing to do with how much you exercise. Which is, again, the argument for getting tested rather than assuming.
General education, not a diagnosis. If your periods have stopped, your GP is the next step.
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