Sit ups are a great way to work your abs, but holding your feet down is an ever present challenge. You could find something heavy to weight your feet down, but things like weights can be cumbersome and not always hold you down when you get aggressive with your tempo. You can always have someone hold your feet down, but this can be an unreliable long term solution.
This is why I’ve built these custom fit foot straps that you simply slip under a door. They are simple, cheap and work like a charm.
Check ’em out and let me know if you have any questions down below.