INDEX


This new column features short items about sport research in progress or in print, highlights of recent or upcoming conferences, hot topics on mailing lists, and anything else of interest to the sport-science community. Content can range from ground-breaking or gossipy. Send a paragraph or two to ferret=AT=sportsci.org. Items will be edited and bounced back to you for approval.

May-Jun
1998:

Palm-top Blood Lab · Abdominal Exercises · Beefing Up to Win  · New Coach, New Plan?


PALM-TOP BLOOD LAB
    High-tech miniaturization has turned metabolic carts into metabolic belts. Now a blood lab fits in the palm of your hand. This report from Gord Sleivert.
    The i-STAT Clinical Analyzer was designed for emergency rooms and intensive-care units, but I think it has potential for sport scientists in the field. The instrument is battery-powered, self-calibrating, simple to use, and has its own error detection system that will indicate if the blood sample is insufficient or if a sensor is faulty. Single-use disposable cartridges containing sensors, a calibration solution, a fluid transport system, and a waste chamber perform the analyses. Cartridges are available for the analysis of sodium, potassium, chloride, pH, pCO2, pO2, bicarbonate, urea nitrogen, glucose, hematocrit, and more. It will work with blood from a finger or ear-lobe. And the data are valid and reliable (Erikson & Wilding, 1993; Jacobs et al., 1993).
    I used an i-STAT recently to monitor elite cyclists competing in the 12-day Tour of Langkawi, in Malaysia. I often encountered temperatures higher than its recommended maximum of 37 °C, but I solved the problem by refrigerating the instrument and cartridges for 10-15 minutes before use. I wanted to track adaptation to heat during the tour, so I monitored a number of blood parameters daily for the increase in plasma volume that occurs with heat adaptation. The figure shows morning sodium concentration and hematocrit during the tour. Judging by the drop in sodium concentration, most of the increase in plasma volume occurred in the first three days. On the basis of the falling hematocrit, plasma volume continued to rise over the next week. The cyclists probably would not have been optimally acclimatized until their hematocrits stabilized.
    The i-STAT may also be useful for monitoring changes in blood during exercise. It does not measure lactate concentration directly, but it does measure bicarbonate, which is inversely related to lactate. There may be other ways sport scientists can use it. Check out the i-STAT website.

Erickson, K.A. & Wilding, P. (1993). Evaluation of a novel point-of-care system, the i-STAT Portable Clinical Analyzer. Clinical Chemistry, 39, 283-287.
Jacobs, E., Vadasdi, E, Sarkozi, L., & Colman, N. (1993). Analytical evaluation of i-STAT Portable Clinical Analyzer and use by nonlaboratory health-care professionals. Clinical Chemistry, 39, 1069-1074.

ABDOMINAL EXERCISES
     Rehab programs for the back focus on strengthening the abdominals. But in an item in the previous issue, we read that scores for bent-knee sit-ups and in the sit-and-reach tests did not correlate with low back pain. A recent paper by Juker et al. (1998) helps resolve this issue. They found substantial electrical activity in the psoas major muscle in all sit-up exercises, while curl-ups had minimal effect on these hip flexors. Activity in the psoas increases compressive and shear forces on the joints in the lower back, which is not good for people with bad backs. Fit individuals should be able to handle them, though.
     The authors concluded that there is no single best exercise to train all the abdominal muscles. The safest exercises that maximize abdominal activation and minimize hip flexor activation are probably curl-ups, cross-curl-ups, and isometric side support.

Juker, D., McGill, S., Kropf, P., & Steffen, T. (1998).  Quantitative intramuscular myoelectric activity of lumbar portions of psoas and the abdominal wall during a wide variety of tasks.  Medicine & Science in Sports & Exercise, 30, 301-310.
Contributed by Duane Knudson.

BEEFING UP TO WIN
     Where will it end?  In the 1920s, 100 kg (220 lbs) was considered enormous.  By the 1960s the average football player's weight was 113 kg (250 lbs).  Today many of these guys weigh around 135 kg (300 lbs).  Some tip the scales at 158 kg (350 lbs), all in the interest of knocking down opponents.  Ferret might eat more than his Wheaties and if it meant earning $15 million, like some of these guys. But is it worth the risk to health?
     Katch and Monahan (1998) have now tracked changes in the build of offensive linemen in the National Football League in terms of their "BMI" (body mass index: weight in kilograms divided by the square of height in meters). From 1920 to 1996, their average BMI increased from 27 to 35. Advanced training techniques, diet, and recruitment of ever bigger individuals have probably all contributed to this increase in size.
     Today these football players are muscular, not obese. But if that mass of muscle turns to fat when they retire, their high BMIs will put them in a high-risk category for many diseases. Some loss of muscles mass is inevitable when they quit the challenge of the football field. Not replacing it with fat mass will be their new challenge.

Katch, F.I. and Monahan, K.D. (1998).  Changes in Body Size of Offensive Players in the National Football League:  A 76 Year Review of 27,744 Players.  Medicine & Science in Sports & Exercise, 30, S239 (Abstract 1359).
Contributed by Frank Katch.

NEW COACH, NEW PLAN?
    Ferret received word that Loren Seagrave is the new coach of Olympic Champion and World Record Holder for the 100 meters, Donovan Bailey.  Seagrave replaces Dan Pfaff from the University of Texas at Austin.  Loren was the Head Women's Track Coach at Louisiana State University, winning five NCAA team championships while Dan Pfaff was an Assistant Track Coach at the same university.
    Seagrave has coached many top athletes including three of the top six American women in history over 100 meters. He is currently a speed consultant to the Atlanta Falcons and is co-author of the Speed Dynamics training system and instructional video series.   He has served as consultant to Athletics Australia and the Swiss National Athletics Federation and has been editor of the sprint and hurdle events for the IAAF Level II World Coaching Education Program.
    Bailey had a competitive event shortly after Seagrave took over.  When asked if he planned any changes before that time, Seagrave said no, he needed to get a feel for how things are going.  Are changes in store?  Chile's Sebastian Keitel shocked everyone by beating Bailey on April 26 at the São Leopoldo meet in Brazil.  Keitel ran 10.10 seconds to Bailey's 10.13.  Bailey's 1996 world record was a 9.84 for the 100 meters.

Contributed by Mary Ann Wallace.


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