"Perhaps the most interesting change we've been privy to so far however is news that Carl will now have to eat in order to maintain his physical state. Through dozens of accurately modelled restaurants and other eateries, the criminal wannabe will be able to top up his stamina meter, and actually visibly gain weight. In fact, he can overdo it. Says Houser, "Playing a mission when you're a fat bastard and everyone call you a 'fat bastard' in the game world is an amazing experience." It makes the mission harder, but Carl can always go to the gym to burn it off, and then head back and blow the dissenter's head off with his newfound dual pistols."
I have found it helpful to do the stretching exercises my physical therapist recommends. Do some core strengthening exercises, such as the ones highlighted at The Mayo Clinic. By keeping your core strong, your back won't put itself in a position to cause that sciatica pain you are having.