Sky Crunches (How To & Alternatives)

Sky Crunches are a simple, but effective core exercise that can offer a bit of variation to regular crunches.

In this article, I’m going to show you how to do sky crunches, what muscles they work and a few variations and substitutions that you can do in place of sky crunches.

How To Do Sky Crunches

Equipment Needed

None

Instructions

Lay flat on your back with your legs straight and also flat on the ground.
Place one hand on top of the other and raise them up, arms straight, straight above your shoulders.
Keep your chin off your chest throughout the entire movement.
Lift your shoulder blades off of the ground approximately 3 to 5 inches and reach your hands directly vertical.
Slowly return to the starting position and immediately repeat the exercise until all reps are completed.

Coaching Points

Many athletes will reach their hands down towards their midline instead of straight up into the air. Try to reach for an imaginary object directly vertical of your shoulders.

Focus on the squeeze of the contraction at the top of the rep. It’s easy to mindlessly rep through crunches without getting much benefit out of them. Focus on each rep.

Muscles Worked

Sky Crunches primarily work the Rectus Abdominis.

Sky Crunches differ from many other ab exercises because in many ab exercises the feet and legs are elevated off the floor. When this position is maintained, the Tensor Fasciae Latae (TFL) and Quadriceps Femoris are also working due to the legs being held in the air.

By placing your legs flat on the floor instead of up in the air, it removes the workload from these muscles.

This makes Sky Crunches a great option for anyone with a lower extremity injury that would prevent them from being able to elevate their legs.

Best Rep Schemes

So, how many sets and reps of Sky Crunches should you do in one workout?

I like to program Sky Crunches as part of a high volume, bodyweight ab giant set.

For example, a bodyweight giant set would look something like:

Crunches x 25
Oblique Crunch x 25 (R/L)
Sky Crunch x 25

A hundred reps back to back to back is sure to get those abs burning.

Sky Crunch Variations

What to change your workout up just a bit. Here are a couple of Sky Crunch variations:

Weighted Sky Crunches

If Sky Crunches start to become too easy, you can ramp up the difficulty by holding onto a weight.

You can hold a dumbbell or a plate to add some extra resistance to your Sky Crunches.

Alternating Sky Crunch

Instead of reaching up to an imaginary object straight above you, alternate reaching towards two invisible points – one above each shoulder. This reaching side to side movement will incorporate the obliques more.

Sky Crunch Alternatives

If you can’t do crunches, for whatever reason, or you’re just wanting a different ab exercise option – here are a couple Sky Crunch alternatives:

Seated Crunches

If getting down onto the ground is a bit of an issue, you can try Seated Crunches.

For seated crunches, sit down on the edge of a bench with knees and feet close together. Crunch by lifting your knees up towards your chest. Use your hands on the bench for support if necessary.

Toe Touches

Toe Touches are basically the exact same movement as a Sky Crunch, but are done with both feet straight up in the air as opposed to lying on the ground.

Start with your legs vertical and then crunch up, reaching your hands towards the toes.