Skinny Jeans also tones core muscles so gym - goers can zip their skinny jeans . Finally , posture also helps , as are balance and ability to stand back straight . Expert : Johnson likes the concept of the workout . `` Exercises that develop the core muscles are important , '' he says . Like any exercise program , it 's important to start slowly , not get excited .
Skinny Jeans also tones core muscles so gym - goers can zip their skinny jeans . Finally , posture also helps , as are balance and ability to stand back straight . Expert : Like any exercise program , it 's important to start slowly , not get excited .