How To Build a Better Body highlights some of the things you can do - you guessed it - to build a better body.

Stave off sickness. Extreme training regimes can suppress your immune system, but you can counter this by taking extra iron, zinc, and protein.

Balance your diet. Endurance athletes tend to eat lots of low-fat foods, which can be short of vitamin E, and high protein ones, which tend to lack vitamin C.

Supplements of 500 mg per day of vitamin C and 150 mg per day of vitamin E should be enough.

Make you lungs work harder. Lungs can be strengthened just like arms and legs. In a 2005 study, researchers pinched shut people’s noses and forced them to such air through a tube that restricted intake until the subjects’ effort reached 75 percent of maximum capacity.

By making the breathing muscles work harder than usual, peak power increased later during short, sprintlike exertion. At home, you can train with your mouth full of water, which forces you to breathe only through your nose.

Train high and in the heat. At altitude, an athlete in training takes in less oxygen. This stimulates increased production of the red blood cells that transport O2 through the body, leading to better performance back at sea level.

Training in the heat can increase endurance and cause more efficient blood circulation.