Putting your body through intense regular workouts will bring about obvious beneficial results, but if you are starving your body of adequate sleep, this can have the same effect as overworking or over training your body and could result in exhaustion, muscle weakness and may even lower your immune system.
Exercised muscles can only repair and grow stronger when they are allowed to rest completely. Giving your body the chance to rest well after a day of hard work will also allow your brain to rest too and can often relieve the symptoms of insomnia and restless sleep.
Experts tell us that eight hours sleep per night is the minimum you need to function well, but this can vary from person to person. If your job requires you to work long hours or you have changing shift patterns that can interfere with the amount of sleep you get, then you may well find yourself waking up feeling quite sore from your previous days workout. Being able to have between eight to eleven hours of sleep per night is the optimum time to fully recover from exercise and to have the least amount of muscle soreness from the day before.