One of the biggest complaints people have about doing sit-ups is the back pain. Yes, it can be painful if proper form is not followed or what other exercises are incorporated.
Most people try to have an ab regimen each and every workout. And if you just have to get abs in, understand that sit-ups involve your hip flexors heavily. Hip flexors extend from the bottom of your thigh, to the top of your abdominal cavity, and attaches to your spine – which becomes especially tight when fully contracted becomes increasingly tight. A tight hip flexor will pull on your lower back, causing pain. Stretching hip flexors in between sets on the following day can help, or…
On days that you incorporate heavy cardio or on a leg day, you might want to consider an ab workout that focuses on Swiss-ball crunches, machine twists, and stomach vacuums as a healthy alternative.