This. I've been doing more gym work in the last 6 months, and I've maybe only been to an actual gym three/four times, with most of it being resistance work at home or running. My riding has come on leaps and bounds, I've improved more in the last couple of months than all of last year. I know my strength has played a huge part in this, so yeah doing 30 mins of gym work a day at home is a lot more worth while than spending your hard earned cash on a new titanium bolt or the like.