I?m 5?11 & weigh 180lbs and I?m able to do all the workouts on this machine without an issue. , the magnetic clasp would come loose and I felt like the watch would fall off. Would not recharge. Nice to have the Bluetooth feature as this means less cords to get tangled up if shes using it especially when laying down. I have used helmet straps for years and never had an issue. I?m a 7 1/2 to 8 usually and I did have to size up. My advice is to buy literally any other bikini trimmer. 5 or a 9 depending on the shoe). Put a connector on 1 end of 2 long poles. After my meditation audio I listened to some songs.