I do find the first 2 days of my cycle my energy is down, this is mainly due to bad cramps.
They were horrible in my "youth". But completely went away the 3 years I was a vegetarian/vegan. Absolutely no cramps during that time and my cycle was every 35 days and lasted only 3 days. Loved it. Unfortunately, my body was no longer retaining iron and I was fainting 3x a day on average. So vegetarian/vegan not for me. I need my meat! ;-)
They aren't so bad now, and advil &/or tylenol gets me threw most days.
I have the worst timing when it comes to white water rafting weekends and races.
But probably due to the excitement of the activity and a couple of advils I have never had a problem. Activity defintely helps, even it is sometimes hard to get yourself up to do it.
I also use the best invention ever the DIVA cup. So have never felt the need to suppress my cycle.