To become a great athlete at any sport, you need to build up muscle to get stronger legs or arms. When doing this, you need to make sure if you're going to use weights that you don't use too much weight or build up too much muscle.
For volleyball, you'll need to have both strong legs and arms. You need to have the strong legs for when you're staying low, passing ,and also with setting. Then you need the strong arms for serving, setting, and spiking.
When you first start out at volleyball you really don't need to worry about either of them, but after you've played for a while and you know you'll continue to play, make sure you work out both your arms and legs. If you're having trouble deciding what kind of weight training you should do, you may think about picking up some weight training videos for volleyball. You don't even have to do everything they show you on the weight training videos for volleyball, you can pick and choose the things you would like to try.
However, there are very few coaches out there that prefer their players not use weights. Therefore, instead of the weight training videos, you'll have to do some alternative volleyball workouts to keep in shape. These workouts can be whatever you want them to be, even just doing different volleyball drills. Or they could be something like just running and doing crunches. Whatever helps you the most is what you should do!
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