One of the major symptoms of a hangover is dehydration. That’s because alcohol is a diuretic, causing the body to lose more water than it takes in.

Given that our bodies are at least 50% water “we need to be hydrated to feel well,” says PT Emma Obayuvana. “Dehydration when working out is tough. Not only does it make the exercise itself feel harder, but by sweating you’re causing even more water loss, worsening dehydration.”

Personal trainer Janine George points out that when people experience a hangover they very often also suffer from dizziness, headaches and nausea. “This can make it very challenging to negotiate exercise. As well as having the potential to make some symptoms worse, working out when hungover is likely to restrict you from giving your best and could risk injury.”

Hungover? Here’s why going the gym really isn’t a good idea (but a gentle walk might be), according to PTs