Weight training in Boxing and MMA must be done logically and smartly. Traditional "bodybuilding " type of lifting does not typically work well for Boxing or MMA. Functional fitness should be your goal on your strength and conditioning days. Incorporating full body/ballistic core movements and exercises work the best and isolated movements should be avoided. Lighter weights and higher reps are generally what seasoned fighters use when weight training because muscular endurance is your goal in a fight. If your muscles are "pumped" during a fight and you can't move properly, then you are in trouble and at a disadvantage during the fight.
Most fighters will incorporate two strength and conditioning days during one week of training. This allows a good balance between the actual fight training and weight or strength and conditioning training. Many fighters will incorporate their strength and conditioning workouts after there fight training, because their muscles are already warmed and fatigued. This also permits a condensed strength/conditioning workout. Many fighters incorporate kettle bells or bodyweight exercises which are geared towards core and compound movements. As stated above, if traditional weights are used, use lighter weights, higher reps and compound exercises.
- Mike "Kujo" Kurzeja, Pro Boxer