What Is The Cause Of My Hamstring Cramps During The Marathon

Audio Transcript

Welcome to the Runners Connect Xtra Kick Podcast. Today’s question comes from Dan and it’s about marathon cramping. Dan says, “I had two marathons and towards the end of both, I had to reduce my pace considerably and walk after the 20 miles due to a hamstring cramping. I am running my third marathon this April and I wish to beat the hamstring cramping this time. During the race I have always depended on electrolyte drinks provided at aid stations and I take salt pills since I sweat a lot. What can I do?”

Dan, this is a fantastic question because it comes up a lot and I think it really helps us dive into the science about what’s actually happening with marathon cramping. There are two different types of cramps. We have electrolyte cramps, where there’s not enough electrolytes in the body and so the neurons stop firing to the muscle and that’s when you start cramping up, and then we have what we call “overuse cramping” and that’s when the muscle fatigues to the point where it cramps. In this case, Dan likely believes that the cause of his marathon cramping is a lack of enough electrolytes and that he needs to take more electrolyte drinks and salt pills. We can see from Dan’s question that he’s already consuming electrolyte drinks and he’s salt pills. It is likely that his electrolyte and salt levels are much much higher than you would ever need, in order to prevent any type of electrolyte cramp.

What’s likely happening is a fatigue cramp and I think most people listening to this podcast, when we say, “I say cramped in the marathon late in the race” most people assume it has to do with electrolytes. Gatorade, Powerade and all those companies have marketing budgets in the millions of dollars and they market how sweating is going to cause you to cramp and lead to all these performance reductions. While that’s true, it’s almost never the cause in the marathon, because the marathon is such a unique event unless you’re not consuming any electrolytes whatsoever.

It’s very likely that Dan’s cramps are caused from fatigue. The body is a very adaptable organism, and so as major muscle groups get tired, your body will start relying on other muscle groups to take over. Dan says he’s suffering from hamstring cramps and so likely the cause of this is, as he’s running or as you’re running the marathon, you start to lean forward at the waist because keeping your chest back in your shoulders upright, in your spine, in a neutral position and holding that position for two or three hours is a difficult task for your core, your hips, your abdominals, lower back, and your glutes.

Most runners just don’t have the strength to hold themselves in that optimal position for three to four hours. You can hold it like that for 90 minutes, maybe two hours and that’s why you don’t suffer from cramps during your long runs and training. When you start to get out there and start doing it for three to four hours, you lack the core strength and the core work to be able to do that. As a result of this weakness, you start to slouch or lean forward at the waist, and what happens when you do that is you cause your butt to sit backwards to counterbalance the upper body’s forward position. This results in overstriding which is landing on your foot, with your foot out, in front of your center of mass, which we’ve talked about a lot.

This dramatically increases the impact forces that travel up the leg as the foot lands. Overstriding also puts the hamstrings in a very vulnerable position at ground contact, and it forces the hamstring to do more work to pull the leg through, since the glutes [00:06:44] at the bottom of the running stride, when the foot hits the ground. The way that you go forward is that your leg will pull through the ground, kind of like pushing through the ground and that’s how you propel forward. Ideally what happens is the glute is what generates the most power for that movement but if you’re in that slouch position with your hips sitting back, you’re not able to activate the glutes as much as you’d like.

So with the glutes not activated, the hamstring now needs to take over and produce that force to keep you going. As you get later in the race and you start slouching more and more, the hamstring starts doing more work and eventually, because it’s been doing more work than it’s used to and also for longer periods of time, the hamstring will start to cramp because it’s getting overloaded. That’s probably what’s happening to Dan.

I bet if we took a picture of you at mile one of the race and a picture of you at mile 18, before you start cramping, you would see a dramatic difference in your running posture. At mile 18 you’re probably leaning forward more at the waist, to compensate for the fact that you just lack some of the stability to keep yourself upright. If you have calf cramps, there are other reasons for that.

We have a couple articles on the website that can go into some specifics. We have a video series for insider members. If you’re not an insider member, just head to anywhere on runnersconnect.net and you can sign up for Runner’s Connect Insider. There’s places to sign up all over the place, usually on the side bar or on the bottom of an article. Sign up and you’ll have access to all of the stuff that we talk about on this podcast. If you are an insider, you can head to your courses tab and in those courses tab you’ll see a 3-part part course on improving your form. In video three, we talk about marathon cramping specifically and we give three or four different areas where marathon cramping is impacted by different areas in your form where you need to improve. Maybe you’re slouching or you suffer from lack of hip extension, etcetera.

In terms of what we can do about it, that’s where we get into designing a training schedule that’s very specific to you, and from a strength training perspective, you really want to work on the hamstring strength in general. That will help because that is the end result of the problem. Your hamstring lacks the functionality or the strength to do it so shrinking the hamstring can help. Most importantly, we want to strengthen your core. Work on strengthening your core and your hips and work on your glut strength. Make sure that you are already running with good posture. If you do those things for your coming race in April, that’s probably going to prevent your cramping.

If you can get through the early part of the first three-quarters of the race with a strong posture, without leaning forward, keeping your form where it needs to be, then you’re going to be okay. Now you’re not putting any excess pressure or any excess demands on other parts of your body that you haven’t necessarily trained as much. Keep that in mind and start including that core hip and glut workout in your training. That’s going to eliminate your [inaudible 00:09:59] cramping.

I hope that helped answer any questions you had about marathon cramping and gave you an idea that you need to look outside of electrolytes, in order to make sure that you’re getting the most out of your training, if you suffer from cramping.

If you have a question, you can head to runnersconnect.net/daily and you can click the record voicemail button and send in your question and we will answer on the podcast. You can also start your free two week trial of our training plans at runnersconnect.net/train where you can get a customized schedule, coaching support and we will connect you with our community of like-minded runners who are either training for the same race or in the same boat as you when it comes to the training difficulties or the training challenges that you experience.

Thanks so much for listening guys. I really appreciate it.