How to increase Cardiovascular endurance?
I've been training in MMA for a while now. I took some time off and got into bodybuilding but I've been back to MMA for the past 5 months and my endurance is way lower. I did put on a lot of muscle which i know takes more oxygen to keep going but I'm struggling with my cardio lately. I started running and doing 3 miles and I'm dying to complete it. Before I could run 10 miles without gassing. Are there things I can do to get my cardio back or do I just need to keep running and training and it will eventually improve?