I’m 16 and starting to get into MMA. I have been taking karate since I was 10 and now am learning jiu jitsu. I am 5’8” and only 135 pounds and I want to add at least 20 pounds to my frame. I want to start lifting weights to bulk up but my jiu jitsu instructor told me that too much lifting could lead to stiff muscles. Is this true?
First let me say that I absolutely believe that weight training will improve your performance in martial arts, as it can in most any athletic endeavor. With greater strength comes greater control, greater confidence and greater ability to move opposing forces. I wholeheartedly encourage you to lift in conjunction with your martial arts training.
As to your instructor’s views – there is some truth to them. Lifting weights, especially in the beginning, can bring about sore, stiff muscles. This is a natural byproduct of exercising, but a temporary one. To avoid DOMS (delayed onset muscle soreness) from interfering with your jiu jitsu classes you may want to schedule your weight training workouts such that you have at least a day between them and martial arts.
That being said,, weight training will not stiffen your muscles over the long term, especially if you are conscientious about regular stretching, which I know is part and parcel to martial arts training.
The benefits you will see from regular weight training will be great while the negatives will be minimal at best – I promise you that.