Yeah i thought about the possible punishments i could do, for example whipping myself on the back or punching myself in the face...but as you can tell they're not really enforcing anything positive, just self-hate. On the other hand cold showers are actually beneficial, they increase adrenaline/dopamine levels and make you more awake. Exercise in general increases Neurogenesis and addictive behaviours have lots to do with the level of dopamine-2-receptors in the brain. It's found people with less D2 receptors usually have less self-control. So learning new things and exercise could possibly help create new neurons and ultimately improve self-control.