Novices and newbies discussion

Hi Everyone! Firstly, I would like to say how envious and proud of how some people can go months or even years in chastity. Personally, my longest has probably been 3 days. Mostly because I have no self control. So a little bit of background. I am fairly active, going to the gym 2-3 times a week and doing mixed martial arts also 2-3 times a week. There are times when you take someones back and your nuts get squashed or there are times when a knee gets dropped there. So when I do go training, the device or belt comes off. Sometimes a box/cup is worn, but a device/belt hinders that. So basically, I can only lock myself up on Saturday to Monday. Sometimes I wish I have a keyholder in real life, who can lock me as soon as I get home, and release me before training. Another thing is, my cage keeps sliding off, even with the smallest ring size. Upgrading to belt helps, but contact sports and tight clothing is not a good idea. So for those who are athletic, such as myself, how do you stay locked up?