My coach says that sometimes im very conservative with my punches and i perform better the times when i let my hands go but i get tired quickly so i go back to counter-punching and taking my time with my punches. What is the best way to improve this?
do training on bags where you throw lots of punches, do it in sparring, do it in everything get super fit and it should be easy
The training tool isn't definitive when designing a conditioning workout. The MOST IMPORTANT aspect of any conditioning workout comes from within. It don't matter if your running, rowing or punching. Turn up the intensity and your conditioning WILL improve.
I didn't say anything about fighting, so the Ali - Foreman reference bears no meaning. Reread my post and note that I talk about "conditioning workout". My point was to turn up the intensity of the workouts, to facilitate improvement in work capacity. Bust a gut in the gym, and your work capacity will improve.