Endless crunches are worse than a waste of time, they can even create an imbalance and dysfunction!
When I was a barely an adult, I gained a bunch of weight and just tried to suck in my gut all the time, trying to hide it. This really messed with my breathing and my mind, due to the breath connecting the sympathetic and parasympathetic systems (Fight or Flight and Rest and Digest respectively). I found yoga and the science behind it and stopped sucking in my gut for a few decades. I did have nice abs from time to time with a lot of work and strict dieting, usually burning out shortly afterward. I developed dysfunction in my back and the pain that comes with it. I have friends with killer washboard abs and terrible back problems. I think that everyone, at one point or another, wanted washboard abs. The road racing greats said to let the belly hang to get a more complete filling of the lower lungs, where there is more O2 and CO2 transfer, due to more capillaries, which seemed to fit in with the teaching from yoga.
Contrary to my title, I do believe that a strong functional core is vital to riding and most other life activities. The key word is functional! And I don't mean doing back extensions to balance the abs or even regular planks, the position between many of the named poses in the yoga sun salute.
Yoga teaches you how to breath as you move. I may have missed it in all my years of study, but that was one key piece of information that eluded me. Years ago, I got a clue. When getting certified as a personal trainer, I learned about lordosis or sway back. It seemed kind of mundane to a young guy wanting to get big and strong; how wrong I was!
Fast forward many years and I was mostly keeping my back in check, mostly. I tried chiropractic for some time. I would get put back in place, but without strengthening the weak muscles and loosening the tight muscles, I was doomed to fall out of alignment sooner or later, hence having to go back and get cracked one to three times a week. That is when I restarted my yoga and it helped. I stopped getting adjusted after a doctor blamed my neck degeneration on the repetitive adjustments. Not sure if it is true, but it scared me off of chiropractic, except for an emergency. I know this is not their business model. I went along pretty well for years, as long as I got in at least one yoga session a week. My body would usually let me know, gently, in a timely matter if I missed a session. Well, there was a time that I seemed fine and I went a few weeks without yoga, everything was going swimmingly and then the worse pain that I have had in a very long time occurred, if not the very worse ever. I went in for an emergency chiropractic adjustment and the chiropractor put me on a machine that checked your alignment. After it lit up like a Christmas tree, he said I was pretty messed up and would need weeks or months of follow ups, and of course he had a plan. After the adjustment I did a light yoga session and then every day until the next visit the following week. The chiropractor put me on the machine and was astonished that hardly any lights on his machine came on. I learned my lesson and never went a week without yoga, until I learned and practiced proper form on certain kettle bell drills and stretches. More on that later.
Again, I thought I had it figured out. Last year I had a pretty good Single Speed riding, foam roller and Kettle Bell training plan for Cohutta 100. I was short on time, but I came along really well and did great for a metric century. Unfortunately, I signed up for the hundred miler not a hundred kilometers! I was geared too high, got cocky from the training, my standing riding was mostly exhausted and my right lower back started screaming at me, pushing the big gear mostly seated.
Some time afterward, I was cleaning out old photos from my phone and had one of me bending over, marking a road race course with paint. From the angle I could see that there had been a problem for some time. There was a stiff part that forced the spine above it to bend more than it should. I looked at my program with this lens and removed any suspect movements. It did not help that I had a crash over a year before that was still affecting the movement pattern of my left shoulder, forcing some compensation in the right lower back, particularly overhead, but that is yet another story.
I was developing a program for an athlete of mine. As I would hardly ever see her, I looked for videos of the drills I wanted her to do on line. She was going to be doing mostly body weight or low weight drills, due to time and access to equipment. I wanted to make sure she was getting the form correct. Some of the best I have found that are mountain bike specific are from James Wilson. But during my Youtube search, videos from Strength Side kept popping up. Strength Side is mainly about the core power lifting moves, at least from the videos I have seen, squats and dead lifts, etc. He talked about Lordosis and what struck me was the concept of bracing to keep your hips aligned deep in a squat. I had gotten good, maybe too good at the hip hinge that is associated with the dead lift and swing and seated riding and all the sitting that life throws at you makes your hip flexors tight. I knew about the hip flexors, but keeping them loose was only part of the puzzle.
Tight hip flexors tip your pelvis forward, by slightly flexing the femur/pelvis joint and slack lower abs let this happen. So it comes back to that mundane Lordosis, Strength Side says it best, that it just comes down to basics that people would rather skip.
But what about the breathing? Luckily, I recently came across James Wilson explaining Crocodile Breathing. Crocodile breathing is still diaphragmatic breathing, but you remain braced and let the sides and the back expand more than the front, no more hanging belly.
So ironically, it seems that I come full circle to sucking in my gut. To quote the band Cake's song Comanche; "You need to straighten your posture and suck in your gut. You need to pull back your shoulders and tighten your butt.", but with proper breathing.
I should have listened to my mother and straightened my posture, but no one ever explained how to me or I was not ready to hear it.
Great, you may say, but what the hell does this have to do with mountain biking?
Many mountain bikers just want to ride their bikes and have fun and fitness seems to be a four letter word, read an article that puts it in perspective here.
But really it comes down to bracing to keep the hips and spine aligned. One of the coaching cues on the Heel Tap drill is not to suck in the gut, but to press the small of the back into the ground using your abs to tilt your hips back, or down in this case. I was very weak in this movement pattern. My back would actually click if I did not practically cramp my abs to hold my spine down! Now I was on to something! Along with Strength Sides; Staying Tight in the bottom of a Squat, I came to understand, train and change my bad habits and "You need to straighten your posture and suck in your gut. You need to pull back your shoulders and tighten your butt." When you pull the front of your pelvis up with your abs, your glutes reflexively contract, and both stabilize your spine
I started applying this on the bike and found to my amazement that it really helped. Particularly toward the end of a climb when I normally would be gassed, I felt an extra kick. Or when my back was acting up, bracing would keep it in check. Bracing also helps you keep from bobbing on the saddle at a high cadence seated spin. I started to explain this to a friend, who among other things, is a bike fitter and he immediately thought I was going to say "rock your hips forward", which is the common wisdom of bike fit. I said no, even though, I have described it the same way before also, leaving out the bracing to let the belly hang for breathing of course. There are times that you rock your hips forward, the key is to keep the abs braced to stabilize your platform.
It is easier to understand it from a squat perspective. James Wilson advocates standing up as the primary power position and not the pseudo standing/quasi hovering seated position. He suggests literally a squat, one leg at a time (you push away the pedals instead of the ground). You need to brace your abs while you apply force to the pedals.
Bracing your abs also helps, in the seated position and even more important in the quasi standing hovering over the saddle position. Unlike Bike James, I will not argue the value of each, because I think each is an important weapon to have in your arsenal. It is easy to let the let the abs slack off and be over powered by the rectus femoris (part of the quadriceps) and a tight psoas. Both flex the pelvis, leaving the pelvis unstable, wasting energy and causing a problem in the lower back.
I have a friend that told me to squeeze my abs when I lift heavy objects. Now I know how! When I lift a heavy object, I visualize scooping it up, with my pelvis as the scoop.
Just apply these principles to pedaling a bike.