1) Is this decrease in vertical jump because of your leg pain?
1) You could have something called Neural Dumbness, This definition was created by Bill Piche I believe. What it is, is if your body is used to training daily then all of a sudden you take 2 weeks off when you come back to train again you will feel your strength decrease at first. But once you get back into training you will notice your results increase at a faster rate.
3) This also could be a result of you going into a workout without a positive attitude about a workout.
there are many reasons for this but right now i recommend to start training again.
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