JOURNAL WATCH Journal Watch

ANTHROPOMETRIC ESTIMATIONS OF PERCENT BODY FAT IN NCAA DIVISION I FEMALE ATHLETES: A 4-COMPARTMENT MODEL VALIDATION. Moon JR, Tobkin SE, Smith AE, Lockwood CM, et al. Journal of Strength and Conditioning Research 2009;23:1068–1076.

The equations based on two-compartment models that are used to

estimate body composition are not without error. In an attempt to decrease the error associated with anthropometric equations, updated equations were developed using multiple-compartment models. The purpose of this investigation was to determine the validity of the updated equations and compare them with previously validated generalised equations for estimating percentage fat (%fat) in female athletes. Twenty-nine white female National Collegiate Athletic Association (NCAA) division I athletes, aged 20±1 years, volunteered to have their %fat estimated using anthropometric measurements. Skinfold equations included generalised and updated equations and a height- and weight-based equation. The %fat values were compared with a criterion four-compartment model. Results: The results suggest that the updated skinfold equations are valid but not superior to the generalised Jackson et al. equations, and that the height- and weight-based equation of Fornetti et al. are not recommended due to the large individual error in this population. Additionally, more than three skinfold sites did not improve %fat values. Therefore, the Jackson et al. sum of three skinfold equations is the suggested skinfold equation in the white female college athletes.

sportEX comment In the previous issue of sportEX dynamics, Mark Cheetham’s article “Body composition”

explained that there were a number of methods of determining body fat percentage, many involving expensive equipment. He concluded that the skinfold method is valid as a low-budget, easily repeatable test, as long as the tester is competent. This study further confirms the validity of the equations used to turn the measurements taken into body fat percentage results.

DIVISION I ATHLETES’ ATTITUDES TOWARD AND PREFERENCES FOR MALE AND FEMALE STRENGTH AND CONDITIONING COACHES. Magnusen MJ, Rhea DJ. Journal of Strength and Conditioning Research 2009;23:1084–1090.

The questioned addressed was: “Do athletes prefer same-sex or opposite-sex

strength and conditioning coaches?” A total of 275 male and 201 female National Collegiate Athletic Association (NCAA) division I collegiate football, soccer and volleyball athletes were given the “Attitudes of athletes toward male versus female coaches questionnaire”, which was used to assess the attitudes and feelings of male and female athletes towards the gender of their strength coach. Results: A 2×2 multivariate analysis of variance (athlete gender × coach gender) revealed that the male athletes (all football players) were less comfortable with a female strength coach in all regards and preferred to have a male strength coach. Female athletes did not have a gender preference; nor did they

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have any negative attitudes towards a strength coach. The women would be productive training with any qualified strength coach, whereas the men would prefer working with a male strength coach, no matter how qualified the female coach.

sportEX comment It is a pity that the male participants

were exclusively from American football. It raises the question of whether or not their attitude is prevalent in other male sports. It would be great to repeat the study in other countries. In the meantime, the authors suggest that male athletes be exposed to female strength coaches much earlier in their sport experience: this might help to reduce gender bias later in their athletic careers.

EXPERIMENTAL MUSCLE PAIN DURING A FORWARD LUNGE: THE EFFECTS ON KNEE JOINT DYNAMICS AND ELECTROMYOGRAPHIC ACTIVITY. Henriksen

M, Alkjaer T, Simonsen EB,

Bliddal H. British Journal of Sports Medicine 2009;43:503–507.

This was a randomised cross-over study to investigate whether the knee-joint dynamics during a forward lunge could be modulated by experimentally induced vastus medialis pain. Twenty healthy subjects performed forward lunges before, during and 20 minutes after induction of experimental quadriceps muscle pain. Muscle pain was induced using hypertonic saline (5.8%) injected intramuscularly. Isotonic saline (0.9%) was used as a control. One subject was excluded during data collection. Three-dimensional movement analyses

were performed and inverse dynamics were used to calculate joint kinematics and kinetics for ankle, knee and hip joints. Electromyographic (EMG) signals of the hamstrings and quadriceps muscles were recorded. Results: During and after pain, significant decreases in knee-joint dynamics and EMG recordings were observed.

sportEX comment

This is yet another study whose results could be predicted by anyone involved in sporting performance, but it is good to have high-grade evidence. It shows that local pain in the quadriceps is capable of modulating movements with high knee-joint dynamics. The results may have implications in the management of muscle pain and prevention of injuries during activities involving the knee joint.

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