Tuesday, June 22, 2010

Things Learned from the Philly Bike Race: Part II

I get a lot of questions about cramps. Muscle cramps. Leg cramps. Can you stop my cramping? Sure, but first let's review one of the most common cause of cramping and how to figure out if you need to look further into your cause of cramping. There are several causes of muscle cramps including altered stretch receptors, lactic acid build up, hyperventilation and sodium loss. By far, the most common are lactic acid build up and sodium loss. Let's focus on sodium for now. Sodium is an element in the body that exists bound to chloride to make sodium chloride, also known as table salt. The balance of sodium and potassium ions keep many cells alive and functioning well. Sodium plays a large role in muscle function to make muscles contract.
Sodium unfortunately has a been given a bad rap for its role in high blood pressure. As we look to cut sodium from our diets, we sometimes have a hard time keeping up with our sodium losses. If you've ever tasted your sweat, you know that there is a lot of salt in sweat. If you've ever tasted commercially produced uber-scientific electrolyte drinks, you know that they don't contain as much salt as they'd like you to believe. Different people have different amounts of sodium in their sweat, some more than others, some a lot more than others.

How do you know if you are a salty sweater? Your clothes are caked with salt stains. Look at this guy. He's a pro rider on the Jittery Joe's-Mountain Khakis team. Pay close attention to the salt stains on his sleeves.

Here's a closer picture of his salt stains. If I can see your salt, you qualify as a salty sweater.

Back to cramping.

When salt loss occurs, muscle contraction doesn't work very well. For some, the smaller muscles in the hands and face start to twitch. For others, muscles contract and can't relax.
There are about 10 grams of sodium stored in the body at any given time. A salty sweater may lose all of that salt over the course of long race. When that happens, the cramps come on.

What to do?
If we know how much sweat you lose in an hour of exercise (every pound lost equals 16 ounces of sweat) and we can collect and measure the sodium concentration in that sweat (lab testing), we can figure out how much salt you are losing. From there, we can replace not only the fluid you are losing, but also the salt you are losing. Cramps go away. You are happier than this guy.

Saturday, June 12, 2010

The Philadelphia Sports Medicine Congress

Yesterday, I had the great pleasure of teaching at the Philadelphia Sports Medicine Congress. This is a one-day event that covers a wide variety of sports medicine topics. The course organizers asked me to discuss bike fit, especially from the medical standpoint. One of the things about a proper bike fit that I have always maintained, is that it must be functional. In my seminar groups, I discussed the use of core strength and flexibility to dial in an individualized bike fit.
Almost everyone present readily identified the tightest muscles and the weakest muscles in most people. From there, it was a simple to demonstrate the proper core strength and flexibility tests needed to create a bike fit that allows for both comfort and maximum power transfer.
As bike geometry evolves from "standard" geometry to longer top tubes and compact frame designs, we can rely less upon a standard stem length and seat post type and need to find different ways to keep comfortable on the bike. The importance of core strength and flexibility on bike fit has been one of my interests in cycling, and is something that I have spoken and written about extensively.
It would have been a great seminar for triathletes or duathletes, especially since Ross Martinson of the Philadelphia Runner store was doing a shoe fit running seminar right next to me.

Tuesday, June 8, 2010

Things Learned from the Philly Bike Race: Part I

For the past 12 years, I have been the race doctor for the Philadelphia Intenational Cycling Classic. The sports medicine that I have learned from watching professional cyclists ride 156 miles is way beyond what I can find in textbooks. Some of the things I have learned have become topics of great interest to me, leading to writing of my books and directing the practice of sports medicine for cyclists at the Performance Lab p/b Rothman Institute.

The next few posts will share some ot the endurance sport specific problems that affect even the most seasoned of athletes.

First, a favorite topic of mine: core strength in endurance athletes.

The medical car follows closely behind the main pack of riders. At the back, I can see who is suffering and why. Although it sometimes has to do with fitness, more often than not, it is easy to tell what else is preventing someone from keeping the pace, especailly going up hills.

The "core" is a group of muscles that stabilize the trunk while the arms and legs are moving. Core weakness is especially noticeable when standing out of the saddle. As I tell most of my patients with overuse injuries, "Overuse injuries occur when the exercise demands exceed core strength or endurance capacity."

The same is true for exercise fatigue. A stable core will allow for more efficient power transfer to the pedals, especially when standing out of the saddle.

The medical car passed a group of riders, all of whom had been dropped. As they stood out of the saddle, their hips were wobbling back and forth. Instead of pushing on the pedals, the pedals were seemingly pushing back at them!

Core fatigue occurs even faster with improper bike fit. Most often, the bike fit isn't matched to the core strength. Although low back pain can occur, it is usually weakness and decreased power that results in poor fit.

First Lesson from Philly: Focus on core strength in the off season and make sure that your bike fit matches your core strength. Bike fit for comfort is one thing, but bike fit for power is another and needs to be adjusted accordingly.

Monday, June 7, 2010

Philly Tri Club Seminar

For those of you who are members of the Philadelphia Triathlon Club, don't forget to stop by Kildare's this Thursday for the Maximum Performance Mind and Body Seminar. I'll be discussing the use of VO2max testing for training as well as some of the sports medicine issues for Triathletes. Hope to see you there!

Wednesday, June 2, 2010

Hear The Podcast

The Performance Lab was recently featured in an interview on KYW radio. During the interview, the performance lab and some of the elite training methods were discussed.
You can hear the interview by clicking here