The more blood your body sends to digest your food the less blood is available to go to your muscles, to rebuild and increase strength. You should wait at least 60 minutes after eating before you start your exercise program. Similarly, do not eat too soon after ending your workout because you want the blood that you just targeted into each specific muscle to remain there as long as possible. If you eat food too soon after your workout, the blood will be forced out of your muscles and into your digestive system. So wait at least 60 minutes after your program before you eat a meal.
Speed plays a major role in the incidence of injury as well as strength and muscle development.
Fast lifting creates momentum and doesn't promote blood flow to the muscle. Slow movement creates less momentum and less internal muscle friction. Not only does slow lifting require a more even application of muscle power throughout the movement range, it actually promotes rapid blood flow into the specific muscle you are training. In every strength training exercise for every muscle there are two different parts to each repetition of the exercise set performed. In the bicep curl, this is where you let the weight come back slowly to the beginning position, with your arms extended straight down again.