Gainer's one-piece sauna pants. You can wear them low-rise by dropping the shoulder straps, and adjust them according to how warm your body gets. These are hard-to-find items purchased in the US. Size S. Chacott Sylvia FREED BLOCH capezio Grishko Marty Repetto eleve stina yumiko wearmoi Jewelesque Luckyleo balletmaniacs maldire BalletRosa DellaloMilano (These appear to be brand names.)