Our expert says:
Water changes are likely to explain this. When you're completely inactive, your plasma volume will fall. When you exercise, it increases, and that could easily swing by 1l each way, making up the difference you've noticed (interesting observation, by the way).
It could also be diet related, in that perhaps when you train, you eat more and this actually adds weight. If that's the case, then it's an interesting observation that explains how to lose weight if you want to. And note that this diet change can be sub-consious, you may be unaware it's happening.
The information provided does not constitute a diagnosis of your condition. You should consult a medical practitioner or other appropriate health care professional for a physical exmanication, diagnosis and formal
advice. Health24 and the expert accept no responsibility or liability for any damage or personal harm you may suffer resulting from making use of this content.