in the past half year several times i had heavy muscle cramps in my hamstrings.
mostly when i was in sleep, in the middle of the night. remarkable is that this mostly happens when i took 2 a 3 days rest.
do i train too hard. or could it be that i sometimes use a pre workout shake (with creatine)?
i train CF for 31/2year and CFE for 1/2 year. I do mountainbiking and running.
could someone give some advice which will help me preventing this.