Athletes gym training will vary in intensity depending on what stage of the season they are in. In their offseason competitive bodybuilders focus on building up as much size and strength as possible. They do this by lifting heavier weights for fewer repetitions. They are also a bit more relaxed with their nutrition. Some bodybuilders like to put on as much weight as possible during the offseason and have a long pre-contest diet. This is fine if they only compete in one or two shows a year such as the Arnold Classic in May or the Mr Olympia in September. Other bodybuilders who compete more frequently throughout the contest season try to build as much size as they can while staying close to their contest weight.
Off-season training for bodybuilding tends to be focused more on building size and strength. As previously stated they tend to achieve this by lifting heavier weights for fewer repetitions. In the case of Dorian Yates, he would build up to one working set per exercise for six to ten repetitions. One working set per exercise may not sound like a lot but Dorian Yates would perform up to four exercises per body part and that one working set was so intense that he advised beginners not to follow his training style until they have been training for at least a year. Dorian Yates liked to keep his gym training short and intense then go home and recover.
Other athletes will train in the gym during their off-season to improve performance in other sports. Most of the events in Athletics are short, explosive events with lots of qualifying rounds. The top male sprinters tend to complete their races between 9.4 and 10 seconds. Because of this they will use their weight training sessions to develop power. If a sprinter lacks power, they will spend more time in the gym during the off-season then they do on the track. As the season gets closer they will cut back on the gym sessions and spend more time training on the track. For most athletes, the gym is a tool for improving their performance in other sports.
For bodybuilders the gym is where they train to stimulate muscle growth and the intensity of their workouts will become more intense as they get closer to the contest they are competing in. This can be done in varying styles. Dorian Yates and Mike Mentzer would attempt to complete their workouts in a shorter time using methods such as super-sets and tri-sets. A super-set is two exercises done back to back, Mike Mentzer for example would complete his working set of leg extensions then immediately perform his working set of squats. Bodybuilders like Arnold Schwarzenegger who trained following the high-volume method would perform multiple working sets per exercise and increased intensity pre-contest by reducing their rest periods between sets. If for example Arnold Schwarzenegger rested for 90 seconds between sets in the off-season, pre-contest he would cut that down to one minute. He would also perform super-sets and tri-sets to increases intensity. Pre- contest a bodybuilder is not really concerned with building up their size, rather their concern is to reduce their body-fat so that the shape of their muscles is on show.
Whatever your reasons are for weight training keep in mind that the body needs to be trained intelligently. This way you reduce injury risk and continue to improve.