Puberty the time to build muscles?
I don't have a good weightlift for bench-press but I have a 8kg concrete dumb-bell so I tried to use it as a bench-press but the only place I feel the strain is the part between my elbow and shoulder, And its not the top where the huge muscle bulk is supposed to be. Its the underneath.. There is no strain on my chest
Then I do crunches and then doing some taekwondo leg stretch.. just wanna know if those would help me develop my muscles or help me lose weight because I'm currently 4kg off-scale