THE "BRICK" WORKOUT - GOOD OR BAD? Researchers at the University of Queensland in Australia published a study of triathletes designed to determine whether running immediately after cycling - as in triathlon - has a "neuromuscular control" effect on running biomechanics. They also wanted to discover whether any such effect is related to leg injuries in triathletes. The researchers studied 34 highly trained triathletes, some of whom had suffered past lower body overuse injuries. Testing consisted of comparing running performance [without prior cycling] with "running off the bike" performance. Indeed, some - but not all - of these successful triathletes showed altered muscle patterns (unrelated to fatigue) when running after cycling. Moreover, this was more likely to occur in triathletes with a history of overuse injuries. Although the evidence is only circumstantial, it appears that at least some triathletes have trouble maintaining normal running form immediately after cycling - and this may increase the risk of injury. One possible conclusion: it may raise the risk of injury to engage in frequent or long "brick" workouts, unless you're one of those gifted individuals who can maintain your "normal" running form. The takeaway message: we recommend doing your heaviest training with independent running and cycling workouts. Save your brick training for shorter workouts, when you can concentrate on good running mechanics.
RESEARCH VALIDATES INBODY BODY COMPOSITION ANALYSIS Scientists at Appalachian State University recently conducted tests comparing mulitfrequency biolectrical impedance with hydrostatic weighing (considered among the most accurate methods of body composition testing). Results on wrestlers showed good correlation and accuracy. We welcome this further endorsement of our InBody testing apparatus for measuring body composition.
JURY STILL OUT ON QUERCETIN A number of popular nutrition supplements include Quercetin, a plant flavonoid, as a chief ingredient. Manufacturers tout the benefits of this antioxidant for health and athletic performance. However, most studies - especially with trained athletes - have so far failed to demontrate any significant performance improvements after Quercetin supplementation. A new study looked at 2 weeks of Quercetin supplementation in untrained males. Results showed slight but insignificant improvements in endurance performance. Researchers speculate that Quercetin may help untrained individuals more than athletes; may take longer to show significant benefits; or may really have very little effect on performance at all.
PACING STRATEGIES IN RUNNING HILLS Australian researchers recently studied male distance runners to determine speeds and pacing strategies in running a 9.5-km course with three significant hill sections. Each uphill and downhill section was preceded by a level section - hills were essentially plateaus. Speed and oxygen consumption were measured on each section of the course, to determine runners' self-selected strategies for running uphill, downhill, and level. As expected, runners slowed their pace going uphill and increased their pace going downhill. The changes were largely accomplished by changing stride length, as stride frequency remained fairly constant throughout. Going uphill, runners typically [and subconsciously] slowed their pace to keep their oxygen consumption at or near their anaerobic threshold. Going downhill, however, runners increased pace - but did not approach their threshold levels. This suggests that, going downhill, runners limit their speed based on other physiological factors - perhaps shock absorption or other biomechanical factors - rather than oxygen use. Interestingly, it was observed that after each uphill or downhill section, runners took about 80 seconds to return to their level pace. The conclusions here: • When running downhill, it may be possible to increase speed (and save time) more than most runners imagine, if biomechanical factors can be controlled - i.e. if impact stresses can be attenuated. • If running a little slower (than you think ideal) on uphills allows for a faster return to normal pace when terrain levels out, you may actually gain overall efficiency.
Spirulina - the Next Miracle Supplement? Publishing in Medicine and Science in Sports and Exercise, the research journal of ACSM, scientists demonstrated improved running endurance performance through the ingestion of Spirulina. Spirulina is a supplement made from a specific genus of bacteria, which contains high levels of protein, essential fatty acids, vitamins, minerals, and photosynthetic pigments. Health benefits have been claimed for decades, but little controlled research has been done. In this controlled, double-blind study, runners ingested either Spirulina or placebo for 4 weeks, then reversed treatments several weeks later. For each condition, runners completed a 2-hour endurance run, then a short high-intensity run to exhaustion. After Spirulina supplementation, runners showed a tendency to burn a higher percentage of fat and lower percentage of carbohydrates during the 2-hour run. They also lasted longer during the high-intensity run. It is not known specifically why Spirulina would cause such effects. Although a well-controlled study, this research involved a small number of runners. We would stop short of recommending Spirulina for all runners - yet. But we will be watching for additional research on this intriguing supplement.
Protein May Not Be Needed During Exercise In recent years, quite a few supplement companies have claimed that adding protein to carbohydrate drinks consumed during endurance exercise will enhance performance or increase endurance. Unfortunately, research into this claim has been very limited. In a new study published this month in Medicine and Science in Sports and Exercise (the ACSM journal), researchers at McMaster University in Canada found that protein added to carbohydrate drinks did NOT offer any benefit during cycling exercise (or time trial performance). Using a well-controlled double-blind design, researchers had trained cyclists ride for 90 minutes at 69% VO2max, once drinking a carbohydrate-only beverage and once (at least 7 days apart) drinking a CHO beverage with protein added. Riders also performed a 20km time trial within 24 hours after each exercise bout, to see if either beverage spared glycogen during the endurance ride (i.e. allowed better performance the next day). Results showed NO advantage to adding protein; researchers concluded that consuming sufficient carbohydrate during endurance exercise is all that's required to maintain performance. The only severe limitation of this study is the small number (8) of athletes studied, so the result must be interpreted with some caution. Our current recommendations remain: drink enough fluid to maintain body weight, and take enough carbohydrates to maintain energy levels during a long event. Beyond those basics, let taste, comfort, and experience be your guide to the best sports drink or combination for your training.
Stride Length and Mileage May Increase Risk of Stress Fractures In an effort to quantify the risk of lower leg stress fractures, researchers from Trinity U. in Ireland and Iowa State U. studied 10 male runners during running. Using force data and computer modeling, the researchers determined that increased stride length significantly increases the forces on the lower leg, presumably raising the risk for stress fracture. In addition - not surprisingly - increases in running mileage added to bone stress. Although this study (also published in MSSE) has limitations - it doesn't really tell us what causes a stress fracture in any particular runner - it does make clear the added stress on the lower limbs from increasing stride length. From a practical standpoint, we would simply say that shorter stride lengths may be somewhat safer than longer ones.
Drinking Cold Fluid May Help Performance Recent research suggests that keeping the body's internal ("core") temperature down, by drinking cold (rather than warm or neutral temp) fluids, may improve exercise/athletic performance in warm conditions. Hyperthermia is a significant factor in fatigue, as the body tends to regulate its temperature by moderating output when it gets too hot. You can limit the effect of heat buildup by drinking ice cold fluids before AND during your race or activity. Starting BEFORE the activity actually "pre-cools" the body, allowing greater endurance before heat builds up. Likewise, drinking cold fluids (if available) during the event may also delay fatigue and prevent hyperthermia.
Does Biking Cause Bone Loss? There is conflicting evidence regarding the effects of biking - as a primary mode of exercise - on bone health in aging individuals. As one gets older, the risk of osteoporosis - bone mineral loss - increases, especially among women. Weight-bearing exercise is one of the best ways to help minimize your risk; calcium supplementation and certain prescription medications are also recommended in some cases. However, some scientific studies have suggested [if not proven] that biking may NOT be a preventive weight-bearing exercise, as are walking, jogging, and others. This would be troubling for those of us who enjoy biking as our primary mode of aerobic/cardiovascular exercise. However, the jury is still out on this research - and there is some limited evidence that high-intensity biking, such as sprinting, can act as a good preventive exercise. At SPORTFIT, we believe in BALANCED TRAINING - and this is a perfect example: if you like biking, try to add some other forms of exercise on some regular basis; walking is one of the best (and easiest); weight training is also good for the bones; and jogging is probably the best for bone health. Finally, get your bone density checked on some regular basis after age 50, so you're aware of your health status and can take appropriate measures.
ARMY SEES VALUE OF SCIENTIFIC CORE TRAINING Researchers working with the U.S. Army tested traditional army situp training against the newer functional core training being used by most fitness professionals. The Army has been reluctant to abandon its traditional training exercises, including the situp, arguing (in part) that passing the Army's physical testing requires proficiency in situps - and the only good way to train for a situp test is to DO SITUPS. While the logic in this argument escapes us exercise scientists, the Army was at least willing to allow researchers to test the hypothesis that modern core-strength training would be as effective as traditional situp training - even in improving situp test scores. In fact, the results exceeded expectations: core-strength exercises were even MORE effective at improving situp test scores than was situp training. The core exercises included controlled abdominal curls, bridging, and side planks. There's no word whether the Army will actually change its training, let alone its testing protocols.
This research is yet another confirmation that situps are largely ineffective in training abdominal muscles. It's long been known that situp performance is significantly influenced by the hip flexor muscles, thereby reducing the training effect on the abdominals.
Individualized Training is Key Publishing in Medicine and Science in Sports and Exercise, the research journal of ACSM, scientists demonstrates that endurance athletes who use PERSONALIZED training zones - based on individual heart rate and lactate test results - train more effectively than those using average or age-based zones. Researchers used personal results from VO2 max and Lactate testing to determine appropriate training zones, then found that runners training with those personal zones improved more than runners using age- or activity-based zones. This is a great reason to get our VO2 testing and Lactate Balance Point tests when embarking on an endurance training program.
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