Daniel L. Blessing

Disordered eating patterns in competitive female athletes

In an effort to identify risk for disordered eating patterns in competitive female athletes, the present study compared a sample of NCAA Division I female athletes (n = 74) to a college female nonathlete control group (n = 52). Measures included the Eating Disorders Inventory (EDI) (Garner, Olmsted, & Polivy, 1983), the Eating Attitudes Test (EAT) (Garner & Garfinkel, 1979), and body mass. Findings indicated that none of these highly trained athletes had scores indicative of the constellation of disturbances in eating patterns and personality attributes seen in anorexia nervosa or bulimia. Rather, results suggested that the typical college female athlete falls into the normal range with regard to body mass and eating patterns. The competitive female cross-country runner actually may be at slightly less risk for body dissatisfaction than her nonathlete counterpart, whereas the gymnast may be at somewhat greater risk for weight preoccupation.

Lipid-lowering effect of a dietary chromium (III)—Nicotinic acid complex in male athletes

Abstract Exercise-induced chromium (Cr) losses and marginal Cr intakes may place athletes in a suboptimal state for Cr nutritional status, possibly resulting in impaired insulin function. The purpose of this study was to assess the effects of a synthetic trivalent Cr-nicotinic acid (NA) supplement on insulin controlled variables in athletes. Thirty-four college-age male bodybuilders (BB) were randomly assigned to three groups: placebo (P), n=11; 200 μg Cr−1.8 mg NA (1X), n=12; or 800 μg Cr−7.2 mg NA (4X), n=11. Supplements were ingested daily for 8 weeks and training was controlled. Twelve hr fasting insulin, glucose, total cholesterol (TC), triglyceride, HDL-cholesterol, TC:HDL, LDL-cholesterol, and one hr post-challenge insulin and glucose values were determined at pre- and post-supplementation periods. All pre-supplementation values were within normal ranges. ANOVAs revealed two significant interactions. Mean TC in the P group increased from 139.9 to 153.4 mg/dl, yet decreased from 147.9 to 126.8 mg/dl and 159.2 to 131.3 mg/dl in the 1X and 4X groups, respectively (p

Cardiovascular and metabolic costs of forward, backward, and lateral motion.

PURPOSE The purpose of this study was to compare the metabolic and cardiovascular responses of movement in forward (FM), backward (BM), and lateral (LM) directions. METHODS Thirteen athletes with the following characteristics (mean +/- SD) were evaluated: age 21+/-3 yr, height 172.0+/-9.0 cm, weight 62.92+/-9.05 kg, and VO2max 54.13+/-7.42 mL x kg(-1) x min(-1). Subjects were evaluated at 80.45 and 134.08 m x min(-1). A repeated measures ANOVA was used for statistical analysis (P < 0.05). RESULTS At 80.45 m x min(-1), the following respective VO2 mL x kg(-1) x min(-1) and heart rate (HR) beats x min(-1) responses were: FM = 12.42+/-2.29, 113+/-10; BM = 15.95+/-2.45, 132+/-16; and LM = 22.10+/-4.76, 140+/-15. Both VO2 and HR were significantly different between conditions: LM > BM > FM. At 134.08 m x min(-1), the following respective VO2 and HR responses were: FM = 27.15+/-2.51, 146+/-7; BM = 31.33+/-5.77, 168+/-11; and LM = 32.58+/-5.74, 169+/-10. At 134.08 m x min(-1) neither HR or VO2 were significantly different between LM or BM (LM, BM, > FM). Stride length and stride frequency were also significantly different between conditions. These results indicate the variation in the energy cost of FM, BM, and LM.

The physiological effects of bench/step exercise

SummaryRecent investigation of acute cardiorespiratory responses to the current ‘popularised’ style of bench/step exercise has validated its use in improving aerobic physical fitness, particularly in women. However, no marked differences in relative measures of cardiorespiratory demand have been reported between men and women. Instructor data and training investigations further substantiate the effectiveness of bench/step exercise in promoting physical fitness, including upper body strength. However, the energy cost of bench/step exercise can vary dramatically. Important factors include, the selected step height, exercise rate, imposed step manoeuvre, routine format and use of hand-held weights. Hand-held weights may be more useful for men than woman.During training, bench/step exercise has been reported to yield a high incidence of grade I injury complaints, particularly in the calf and shoulder region. However, nearly 90% of these complaints were attributable to acute muscle soreness. Few serious injuries have been associated with the activity. Biomechanical research has shown that the ground reaction forces (GRF) experienced during bench stepping are lower than running and directly related to the step height and type of manoeuvre. In addition, compared with novices, instructors exhibit a moderation in the GRF pattern generated during landing. This suggests that a learning effect has occurred and that teachers yield a more consistent landing pattern. Finally, the activity may be effective in improving body composition, but a consideration of factors related to energy expenditure (e.g. exercise duration and dietary control) appear to be important in regimens prescribed for modifying body fat.

The physiological effects of aerobic dance. A review.

SummaryAerobic dance exercise is currently one of the most commonly practised adult fitness activities. The majority of the research pertaining to this form of exercise supports its application as a valid cardiovascular training alternative, especially for adult females if performed according to the American College of Sports Medicine (ACSM) guidelines. If however, the participant is interested in modifying body composition, training frequency, duration, or efforts toward caloric restriction may need to be increased or altered beyond those employed in the aerobic dance training investigations. The amount of energy expended during a bout of aerobic dance can vary dramatically according to the intensity of the exercise. ‘Low intensity’ dance exercise is usually characterised by less large muscle activity and/or less lower extremity impact, and music of slower tempo. Dance exercise representative of this variety requires a cost of approximately 4 to 5 kcal/minute. Several trials, however, have shown that vigorous ‘high intensity’ aerobic dance which entails using the large muscle groups can require 10 to 11 kcal/minute. The associated training outcomes could be affected by such differences in dance exercise intensity and style.

Iron status of female collegiate athletes involved in different sports.

Iron status was assessed in 70 female athletes aged 18–25 yr participating in collegiate cross-country track, tennis, softball, swimming, soccer, basketball, and gymnastics. No significant differences in mean hemoglobin, hematocrit, serum iron, total iron-binding capacity, transferrin saturation, and ferritin were found among teams. The mean concentrations of each parameter for each of the teams were within the normal ranges. However, several athletes from different sports had suboptimal iron status indexes. Of 17 athletes with a serum ferritin concentration ≤15 μg/L, 8 (4 freshmen, 2 sophomores, 2 unknown) also exhibited low serum iron concentrations (< 60μg/dL) and low transferrin saturation (< 16%). Thirteen (6 freshmen, 3 sophomores, 2 juniors, 2 seniors) of 51 (25%) athletes failed to consume two-thirds of the Recommended Dietary Allowance for iron and exhibited suboptimal serum concentrations of ferritin, iron, and/or transferrin saturation. Of nine athletes taking iron supplements, one exhibited suboptimal iron status. In summary, nonanemic iron depletion was present among female collegiate athletes involved in many different sports and in all years of participation (freshmen, sophomore, junior, and senior athletes). Female athletes should continue to be individually and routinely evaluated for nutritional deficiencies throughout their collegiate athletic careers.

Effects of selected physical activities on health-related fitness and psychological well-being.

To determine the effects of participation in selected physical activities on scores of self-concept, body-cathexis and four items of health-related fitness, 88 women in university physical education service classes participated 3 hr. per week for 8 wk. in one of five activities (aerobic dance, jogging for fitness, swimming for fitness, life saving, and weight training). A total of 108 subjects participated in the study, with 20 students in health science classes serving as the controls. Few differences were noted between the activity groups and the controls on the posttest with pretest scores controlled. Specifically, loggers and aerobic dancers performed significantly more situps than did the controls, and joggers, aerobic dancers, weight trainers, and those in the lifesaving group displayed significantly greater flexibility on the sit and reach test than did the controls on the posttest. None of the activity groups differed from the controls regarding self-esteem, body cathexis, body fat, or the step test scores at posttest.

Is Low-Impact Aerobic Dance an Effective Cardiovascular Workout?

In brief: Ten women performed four different aerobic dance routines in a randomized crossover study to evaluate energy expenditure. The routines consisted of the following combinations: low intensity, low impact; high intensity, low impact; low intensity, high impact; and high intensity, high impact. The women warmed up for five minutes, then did a 20-minute routine. Metabolic measures were monitored by means of open circuit spirometry and heart rates measured by ECG. Statistical analyses showed that for both high and low intensities, the high-impact routines required a significantly greater energy expenditure, regardless of heart rate. Thus for low-impact dance to meet the minimum guidelines for exercise suggested by the American College of Sports Medicine, it should be performed at high intensity.

The physiologic effects of eight weeks of aerobic dance with and without hand-held weights:

There are few reports concerning the physiologic alter ations that occur following a specified period of aerobic dance. Further, no data exist to describe the physio logic changes or potential risk associated with using hand-held weights during aerobic dance. The purpose of this study was to determine the changes in maximum oxygen uptake (VO2 max) and body composition follow ing 8 weeks of aerobic dance using hand-held weights (Heavyhands, AMF, Jefferson, lA). Twenty-eight college females volunteered for the study. All subjects were given a preoxygen and postoxygen uptake (VO2 max) treadmill test. Body composition was measured by taking the sum of five skinfold sites and determining the percent change following training. Subjects were randomly assigned to a hand-held weight or nonhand held weight group. No significant differences (P < 0.05) existed between groups for VO2 max and body com position after 8 weeks of traini ng. However, a significant improvement (P < 0.05) in VO2 max was found within the hand-held weight (37.7 to 42.6) and in the nonhand held weight group (36.5 to 41.9). Complaints from subjects included transient aches and pains in the shoulder area during the first 3 weeks as a result of hand-held weight use. These findings suggest that hand-held weights may be used safely but do not increase the work load sufficiently above that of aerobic dance alone to significantly modify VO2 max or body composition.

Autonomic Responses to an Acute Bout of High-Intensity Body Weight Resistance Exercise vs. Treadmill Running.

Abstract Kliszczewicz, BM, Esco, MR, Quindry, JC, Blessing, DL, Oliver, GD, Taylor, KJ, and Price, BM. Autonomic responses to an acute bout of high-intensity body weight resistance exercise vs. treadmill running. J Strength Cond Res 30(4): 1050–1058, 2016—The aim of this study was to compare postexercise autonomic nervous system (ANS) recovery between a high-intensity training protocol (HITP) and high-intensity treadmill running (TM) in 10 physically fit males. For each trial, ANS activity was measured through the heart rate variability markers of log-transformed square root of the successive R-R differences (lnRMSSD) and high frequency power (lnHF). These markers were analyzed in 5-minute segments at 5–10 minutes of the pre-exercise period (PRE) and during the postexercise period at 15–20 minutes (POST15-20min), 20–25 minutes (POST20-25min), 25–30 minutes (POST25-30min), and 1 hour (POST60min). Plasma epinephrine (E) and norepinephrine (NE) were also examined at PRE, immediately post exercise (IPE), 1-hour post (1HP), and 2-hour post (2HP). The results of this study demonstrate a significant overall time-dependent decreases in lnRMSSD and lnHF (p = 0.003 and 0.001, respectively) in both trials. Trial-dependent differences were also observed in postexercise lnRMSSD and lnHF measures, HITP being significantly lower than TM (p = 0.002 and 0.000, respectively). lnRMSSD at POST60min-HITP remained significantly lower compared to PRE (p ⩽ 0.05). lnHF returned to baseline in HIPT and TM (p = 0.081 and 0.065, respectively). A time-dependent increase in E and NE was observed in both trials at time point IPE when compared to PRE (p ⩽ 0.05). E at 1HP and 2HP returned to near resting levels (p = 0.62, p = 0.26), whereas NE remained slightly elevated in both groups (p = 0.003, p = 0.021). A trial-dependent increase was observed with the HITP eliciting a greater E response (p = 0.025) and NE response (p = 0.03). The HITP causes a greater disruption of the ANS than intensity-matched TM exercise.