are you well hydrated?
There is a difference between drinking water and being adequately hydrated. If you sweat a lot or are doing intense exercise and drinking a lot of water, you want to make sure any electrolytes stay balanced.
One simple thing you can do is add an electrolyte supplement to your water. You don’t need to do it every day, but is beneficial during times of intense exercise and sweating. Adding electrolytes can also help if you suffer from muscle cramps/spasms.