explosive squats.... explosive squats with weights... remember when you do something like a sidehop... your just jumping... it all comes from your legs, your upper body jus helps get the tuck and level the bike off... i just wear a heavy rucksak and jump up my stairs, started doin like 3/4 steps with weight, now i can do like 5/6 lol sweeet and when you go ride, dont just do a sidehop... make it... then end keep doing it, like a workout, till your too tired... then move onto the next thing.. e.g tap's,,, then up to fronts, then back to sidehops. when i ride like this for a while i improve like hell! but the thing is i cba most of the time... especialy when i ride with other people.. we jus have a laugh and take yonks to improve lol