Carbonfiberboy 

Is the OP curious about what helps cycling or general injury prevention or physical appearance? We don't know.

I do full body workouts at the gym twice a week, stretch every morning, and ride my bike. I can plank 2 minutes no problem, but I never do them because why? What's actually going on when one planks? One is forming one's body into a beam. From our engineering education, we know that an evenly loaded beam experiences compression above the neutral axis, tension below the neutral axis, with the loads increasing from the neutral axis to the beam's upper and lower surfaces. In the case of the human body, the neutral axis will be somewhere in the middle of the body. Therefore the spine is in compression, the back muscles are relatively relaxed and the abdominal muscles are in tension, with those closest to the skin under the most tension.

All this won't help cycling at all, which doesn't require much ab muscle, but does require substantial strength and endurance in the back muscles. It does help the 6-pack a little, but not the deep abs which are actually more important for injury prevention and mobility. Gym equipment is designed to target many specific muscles and muscle groups and I get good results from using it.

Transverse abdominals are what you really want to work: https://www.livestrong.com/article/4...inis-workouts/
Note that these exercises are done with a straight back. Crunches should never be done. Other good back exercises are the superman and face-down snow angels.

Seattle Forrest

I don't know if the core muscles really do that much for cycling?

I think squats (I do barbell ones) do more for your core muscles than all the situps and planks.

Renegade rows are a good core exercise too, and probably help with cycling because they'll strengthen your shoulders and upper back, both of which play a role in holding you upright in position.

rubiksoval

No. Planks help you do planks. Static exercises like that are inferior to dynamic strength work because of the limited muscle engagement/range of motion.

Flip Flop Rider

good replies. I was not really wanting to improve cycling through core development.

cycling is my primary mode of exercise but it doesn't hit the core very hard so was really looking for something to supplement the riding

I do some minor arm work outs also because of the way pro cyclists upper bodies look on tv

KraneXL

Well everything's connected to your core. In any event, a good weight training regiment (which everyone should have to some degree) should accomplish that goal -- including the core.

wolfchild

If you lack upper body development and strength, then doing direct arm work is waste of time and energy...Your time would be better spent doing a few different compound exercises that work all muscle groups plus your core at the same time. Work on building your foundation.

Carbonfiberboy 

Unless you're a bodybuilder training for a show, as posters above have written, there's no need for much specific core work. Correctly done strength training work will take care of your core. If you are interested in strength training, there's a good thread over here: https://www.bikeforums.net/training-...e-athlete.html
(IMO since I started it.) The thread even has progressive workout routines which I've adapted from reliable sources and have been using for a few years. My wife says I look pretty good.

Flip Flop Rider

will check it out thanks!