What type of plank is harder?

Related questions

1. Can I do lower back exercises everyday?
2. What are plank walks?
3. Do Superman's work your back?
4. Is Climbing stairs bad for lower back?
5. Is planking everyday good?
6. How many reps does Superman have?
7. Is cycling bad for your knees?
8. Why does my back hurt in the morning?
9. Is low plank or high plank harder?
10. What does Superman plank do?

Tags

1. #elbow
2. #straight
3. #challenge
4. #finding
5. #focus
6. #forearms
7. #difficult
8. #hands
9. #plank
10. #perfecting