So I'm going to demonstrate for you how to do a spiderman plank, it's a progression off a regular prone plan. So, the first thing you're going to do is get into a forearm position, here. Make sure your elbows are aligned with your shoulders.
You're going to lift your knees off the ground, you're going to make sure that you're engaging your core. Your pelvis is tucked under. You're going to raise your right knee up to your right elbow. You're going to alternate your left knee up to your left elbow. So, you can to this for timed sets, 30 seconds, 45 seconds, or you can go 15 reps on each side. It's totally your call.
It depends where you are in your fitness level. You can progress doing a spiderman plank first doing a regular prone plank. If that becomes too easy, then you can do your spiderman plank. And that''s how you do a basic spiderman plank.