August 24, 2007 - Newsletter Issue 49

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Feature Article: Seven Ground-Breaking Studies for Endurance Athletes

As a coach and adviser to hundreds of endurance athletes, I constantly pour through the latest research to find key studies that provide valuable training and lifestyle information for performance success. Here are seven of the latest research studies that could directly affect your training and performance.

1) The Effect of Creatine Loading on Weight and Temperature Regulation

Creatine has long been recognized as an effective ergogenic aid for both endurance athletes and power athletes, and this study inspected how creatine loading (ingestion of certain amounts of creatine for an extended period of time) affects "thermoregulation". It has been suggested that the water gain associated with creatine actually enhances the body's ability to cool, since the body relies on adequate hydration as a cooling mechanism. Conversely, dehydration is associated with greater heat storage and reduced ability to tolerate heat strain. In this study, creatine loading consisted of 20 grams/day for 6 days. Subjects gained an average of 2.86 pounds of intramuscular water weight when supplementing with creatine. But while sprint performance improved, there was no effect on the body's cooling mechanism. Is the potential decrease in power:weight ratio caused by the increase in water weight worth the improved performance for endurance athletes? In a lean athlete who seriously needs to enhance power and force production, I would argue that creatine supplementation can be effective. Additionally, certain types of creatine cause less water weight gain with equal improvements in performance. Look for lipophillic creatine. I use Kreaceps from Millennium Sports.

2) The Effect of Protease Supplementation on Delayed Onset Muscle Soreness.

Delayed onset muscle soreness is the dull pain that you feel typically 24-48 hours after a training session. It is typically caused by muscle fiber micro-tearing, swelling and disruption of muscle fiber "tubes", inflammation, and damage to other intra and extra cellular components of the muscle. Oral enzymes might reduce inflammation by improving return of blood flow from the muscle, thus reducing swelling, and decreasing production of pain molecules called prostaglandins and eicoasnoids that occur after muscle injury. Protease is one of these enzymes that has been suggested for muscle soreness control. In this study, protease aided in the recovery of strength, but did not decrease perception of pain or blood markers of muscle damage. Therefore, in an athlete who needs to return to activity immediately after a difficult training session, protease may assist with force production by the sore muscles.

3) Carbohydrate-Protein Gel vs. Carbohydrate Gel

It has been proven that consumption of a beverage that contains some amount of protein mixed with carbohydrate can provide better recovery and enhanced performance for endurance athletes, when compared with a beverage that contains carbohydrate only. This study examined a similar scenario using gels and endurance cyclists. The carbohydrate:protein ratio was 5:1 in the gel, so if a gel had 100 calories of carbohydrate, it would contain 20 calories of protein. Creatine kinase, a marker of muscle damage, was significantly higher in the carbohydrate-only gel group. In addition, subjects were able to ride 13% longer when training at 75% of maximum (the ride was about 2 hours long). There is no denying the ergonic benefits of protein supplementation *during* a training session. I use a protein-carbohydrate beverage supplement called Perpetuum (made by Hammer Gel Nutrition) during my long rides, and will be keeping my eyes open for new protein-carbohydrate gels on the market after the emergence of this study.

4) Static Stretching and Hamstring Force Production

Previous studies have found that static stretching, which is traditional stretching in which a muscle is held in the stretched position, actually decreases force production of a muscle. This makes sense because a band with greater elasticity, while less prone to tearing, will produce less force. These studies primarily investigated stretching session that last 120 seconds to 1 hour. This particular study, however, investigated a stretching session of 30-60 seconds, and actually found no negative effect on muscle force production (in the hamstrings). I'd be interested to see the application of such a study in running speed for a 5K or 10K, or cycling for a 40K, rather than a simple seated hamstring contraction. I personally perform static stretching every day (incorporating primarily yoga exercises), but prior to any race do not stretch. Instead, I perform dynamic movements like arm swings, leg swings and kicks, squats, and push-ups. These are far more effective at preparing a muscle for the rigors of competition when compared to static stretching.

5) Foot Strike Patterns of Elite Runners

As most endurance athletes are aware, the trend in running is toward a mid to front foot strike and a forward lean while running - as opposed to a heel strike pattern, which actually applies a braking effect to the body. But no studies (up to this point) have investigated runners' foot mechanics during an actual event. In this study, the foot strike mechanics of 415 runners, most of them elite international competitors, were filmed during a half-marathon. As you may suspect, the runners who displayed a heel strike had increased ground contact time and slower speeds. The more a runner's foot strike advanced towards the front of the foot, the less the ground contact time and the faster the run. Interestingly, the fastest runners were also observed to have inverted (toe in) feet at foot strike. It is not clear whether this inversion is a biomechanical gait adaptation, or simply the way that faster runners are genetically built. Regardless, it would be highly beneficial to engage in running drills or hire a running coach to teach you how to run with a forward center of gravity and a foot strike closer to the front of the shoe.

6) Training Intensity and Endurance Athlete Performance

The purpose of this study as to compare two different training programs for endurance athletes. The first training program employed 80% of training as low intensity aerobic training that did not exceed the athlete's anaerobic or lactate threshold. An additional 12% of the training included intensity at heart rate values close to threshold. In the second training program, only 65% of the training was at low intensities, with 27% at close to threshold. Both groups spent the final 8% at very high intensities, close to maximum heart rate. After 5 months, the group that spent more time in the low intensity training improved their 10K running performance by 36 seconds more than the higher intensity training group! This study magnifies the importance of an endurance athlete limiting long periods of time spent above threshold intensity, and instead focusing on a larger amount of aerobic training. This is because the high intensity training reduces the body's sensitivity to catecholamines and sympathetic nervous system response, and also increases risk for chronic over-stimulation and exhaustive stress. I personally spend very little time training at high intensities, but instead stay below threshold for the majority of my training and save the high intensity efforts for the race. If you do not know your lactate or anerobic threshold, it is one of the most important measurements to ascertain!

7) Hot-Cold Treatments for Muscle Soreness

Contrast water therapy has been suggested as a means of controlling the muscle soreness and stiffness, swelling, tenderness, and aching associated with strenuous exercise. In this therapy, an athlete periodically alternates between cold and hot water immersion directly after the exercise bout. This is supposed to cause a "pumping action" as the blood vessels dilate and contrict in response to the temperature alterations. This particular study used 60 seconds of cold water immersion followed by 120 seconds of hot water immersion, alternating between these two treatements for 15 minutes. The contrast water therapy was proven to restore strength and power and improve the recovery of functional deficiencies associated with training. Is 15 minutes of hot and cold water immersion truly practical for the endurance athlete? Probably not in most cases. I personally stand in the shower for 3-5 minutes after an exercise session and alternate between cold and hot water in 15-30 second increments. The cold water can be a shocker, but this effective!

Are you currently looking for a coach to prepare you for the 2008 season? One job of a coach is to take research that is similar to that in these 7 studies, and apply them in your training program. Be confident that Pacific Elite Fitness utilizes only the best training methods and latest research to ensure that you achieve peak performance with economy and efficiency of training. Go to http://www.pacificfit.net/triathletes.html to get started, or contact Ben Greenfield at elite@pacificfit.net to ask more questions.

Until next time, train smart,
Ben Greenfield
Pacific Elite Fitness

www.pacificfit.net - 208-883-7705 - elite@pacificfit.net - 111 S. Neyland #4, Liberty Lake, WA 99019