Here are the 5 common mistakes to avoid while doing planks.
1. Looking straight up
Make sure your neck is relaxed and look at the floor. Do not look forward
2. Too much strain on shoulders
Make sure the elbows are underneath the shoulder. During a plank you should feel the belly muscles and not the top of your shoulder blades. Make sure there is no over activation of upper trapezius.
3. Rounding of upper and mid back
Ensure the thoracic (mid back) spines are not rounded.
4. Arching of low back
Avoid sagging of the low back. Tuck your navel inwards, activate your core and do not hold your breath.
5. Hips too low
Avoid sagging of the hips by contracting your buttock muscles.
It is very common to have a good form at the beginning of the plank. But check yourself at the end of 60 seconds!