I used to run a revised martingale system on the horses. Wish I had done more research into it before I put it into practice.

I turned a £100 starting BR into just over £7k over the course of about 3 months before hitting a horrible losing streak one day when 7 short odds favourites lost in a row, wiping out almost my entire BR. The stress levels where somewhat high that day! I just stick to poker these days, far less stressful