Easy, fast, and simple. No hassles - just show them your voucher and you fill up a form and then you are in. The gym is nice and clean and the facilities are one of the best available in Indonesia. The only minus is the high price - buy being a foreigner, most gyms will try to rip you off anyway. So better stick with this one - it's a little pricey - but you know you are not getting ripped off.