Sleek spinning studio became a mini-chain in a snap. Addictive classes combine stationary cycling with weights and core exercises, pumping music, a little inspirational gobbledygook for a full-body workout. SoulBands a special torture: reps with resistance bands anchored to the ceiling while maintaining heart-failure speed. Teen classes seek to strip the bicycle of its leisurely, banana-seat connotations forever. Lovely clean white spaces, often with orchids, but showers and maybe some free Kiehl’s would be so welcome.