Bodybuilding is a challenging and demanding sport. While the payoffs can be immense, both in terms of physical appearance and professional success, there are also risks. People involved in the sport can experience serious mood swings as a consequence of the bodybuilding lifestyle. There are several factors that can contribute to this.
Bodybuilding can provide a lot of excitement and a real sense of achievement. Bodybuilders can experience euphoria if they achieve a personal record for a particular lift or if they reach a milestone in their training, such as reaching a certain level of body fat or seeing muscle striation for the first time. Combined with the post-workout endorphin rush, stress reduction and the satisfaction of seeing the muscle "pump" after a hard workout, it's little wonder that many bodybuilders experience a natural "high" on a regular basis.
The natural opposite of the euphoric state is depression. Bodybuilders can experience depression soon after a sense of euphoria. Maybe they missed a lift they thought they would complete easily or they are not seeing progress toward their physique goals as quickly as they would like. This can be compounded if they are training extensively -- such as doing two workouts per day. This type of training schedule is extremely demanding, and it's easy for a bodybuilder to become fatigued and even overtrained if they are not giving enough time to rest and recovery.
The Draining Deficit
Many bodybuilders eat at a caloric deficit in preparation for a competition in order to reduce their body fat as far as possible. Their training regime usually stays at the same intensity during this "cutting" phase or even increases in intensity. This puts an immense amount of pressure on the body. When this happens, bodybuilders often experience very low energy, distraction and increased moodiness. This can be exacerbated by reductions in training performance, as their bodies simply don't have enough energy to complete lifts at the same level as when they are properly fed.
The Risk of Overtraining
If a bodybuilder has been competing for a long time, they can develop overtraining syndrome. This tends to occur when a demanding training schedule is paired with insufficient sleep, limited social time and caloric manipulation. Overtraining can cause similar mood patterns to depression, sapping the bodybuilder's motivation and enjoyment for bodybuilding. When this happens, bodybuilders can experience insomnia, lack of concentration and regular, drastic mood swings. Treating overtraining requires a few months of a significantly reduced training load, eating sufficient calories, plenty of rest and time away from the gym.