Quick fact. Ready? After about 2 hours of prolonged training is when our body begins to dip into protein as 5-15% of our energy source. These proteins, in particular, are our BCAAs, which are stored in the muscles themselves.

Quick fact. Ready? Your heart beating is actually the pressure and sound generated by the valves between your heart chambers opening and closing.

Quick fact. Ready? Sweating removes the water that exists in the blood plasma. This makes the blood thicker, and ultimately harder to pump.