This study examined the influence of test duration and anaerobic capacity on VO2max and the occurrence of a VO2 plateau during treadmill exercise in 25 boys (10.4 ± 0.8 years). Protocols with 1-min (P1) and 2-min (P2) stages, but identical speed and grade changes, were used to manipulate test duration. On separate days, VO2max was measured on P1 and P2, and 200-m run time was assessed. At maximal exercise, VO2, heart rate (HR), and pulmonary ventilation (VE) were similar between protocols, however, respiratory exchange ratio (RER) and treadmill elevation were higher (p < .05) on P1 than on P2. Plateau achievement was not significantly different. On P1, there were no differences between plateau achievers and nonachievers. On P2, test duration and 200-m run time were superior (p < .05), and relative VO2max tended to be higher (p < .10) in plateau achievers. Indices of aerobic and anaerobic capacity may influence plateau achievement on long, but not short duration tests.
Glen E. Duncan, Anthony D. Mahon, Cheryl A. Howe and Pedro Del Corral
Nicola C. Sutton, David J. Childs, Oded Bar-Or and Neil Armstrong
The purpose of this study was to develop a nonmotorized treadmill sprint test (ExNMT) to assess children’s short-term power output, to establish the test’s repeatability, and to compare the results to corresponding Wingate anaerobic test (WAnT) measurements. Nineteen children (aged 10.9±0.3 years) completed 2 ExNMTs and 2 WAnTs. Statistical analysis revealed coefficients of repeatability for the ExNMT that compared very favorably with the WAnT for both peak power (26.6 vs. 44.5 W) and mean power (15.3 vs. 42.1 W). The validity of the ExNMT as a test of anaerobic performance is reflected by significant correlations (p ≤.05) with the WAnT (peak power, r = 0.82; mean power, r = 0.88) and reinforced by the relatively high post-exercise blood lactate concentrations (7.1 ± 1.3 vs. 5.6 ± 1.5 mmol · L−1 for the ExNMT and WAnT, respectively). This study has developed a promising laboratory running test with which to examine young people’s short-term power output.
Jorge Zuniga, Terry J. Housh, Michelle Mielke, Clayton L. Camic, C. Russell Hendrix, Glen O. Johnson, Dona J. Housh and Richard J. Schmidt
The purpose of this study was to cross-validate the fat-free weight (FFW) equations derived on nonathletic children and adolescents for estimating mean power (MP) and peak power (PP) in high school wrestlers. One hundred and three male high school wrestlers performed the Wingate Anaerobic Test to estimate MP and PP, as well as underwater weighing to determine FFW. The follow equations were used to estimate the MP and PP of the wrestlers in the current study.
MP (W) = 9.3 (FFW) − 109.8 EQ.1
PP (W) = 14.1 (FFW) − 162.1 EQ.2
The results in the current study indicated that as percent of the mean values, the equation that predicted MP resulted in a substantially greater total error (TE; 19.9% of the mean) than the equation that predicted PP (8.3% of the mean). These findings indicated that the equation that was derived on nonathletes did not accurately estimate MP in the high school wrestlers. The equation for estimating PP, however, was valid when applied to the current sample of high school wrestlers. These findings supported previous studies that have shown that in adolescent males, exercise training improves the metabolic capabilities of the anaerobic glycolytic system, but not the phosphagen system.
Justine J. Reel, Sonya SooHoo, Holly Doetsch, Jennifer E. Carter and Trent A. Petrie
The purpose of the study was to determine prevalence rates of the female athlete triad (Triad), differences by sport category (aesthetic, endurance, and team/anaerobic), and the relationship between each of the components of the Triad. Female athletes (N= 451) from three Division I universities with an average age of 20 years completed the Menstrual History Questionnaire, Injury Assessment Questionnaire, and the Questionnaire for Eating Disorder Diagnoses (Q-EDD; Mintz, O’Halloran, Mulholland, & Schneider, 1997). Almost 7% of female athletes reported clinical eating disorders, and 19.2% reported subclinical disordered eating. Disordered eating was prevalent in all three sport categories with no significant differences between groups. Muscle injuries were more prevalent in team/anaerobic sports (77.4%) than the aesthetic (68.1%) and endurance groups (58.1%). Furthermore, those athletes with menstrual dysfunction more frequently reported clinical eating disorders (1.4%) and sustained more skeletal injuries (51%) during their athletic career than athletes with regular menstrual function. Clinical implications and further research directions are addressed.
Gina Sobrero, Scott Arnett, Mark Schafer, Whitley Stone, T. A. Tolbert, Amanda Salyer-Funk, Jason Crandall, Lauren B. Farley, Josh Brown, Scott Lyons, Travis Esslinger, Keri Esslinger and Jill Maples
High intensity functional training (HIFT) emphasizes constantly varied, high intensity, functional activity by programming strength and conditioning exercises, gymnastics, Olympic weightlifting, and specialty movements. Conversely, traditional circuit training (TCT) programs aim to improve muscular fitness by utilizing the progressive overload principle, similar movements weekly, and specified work-to-rest ratios. The purpose of this investigation was to determine if differences exist in health and performance measures in women participating in HIFT or TCT after a six-week training program. Recreationally active women were randomly assigned to a HIFT (n = 8, age 26.0 + 7.3 yrs) or TCT (n = 11, age 26.3 + 9.6 yrs) group. Participants trained three days a week for six weeks with certified trainers. Investigators examined body composition (BC), aerobic and anaerobic capacity, muscular strength, endurance, flexibility, power, and agility. Repeated-measures ANOVA were used for statistical analyses with an alpha level of 0.05. Both groups increased body mass (p = .011), and improved muscular endurance (p < .000), upper body strength (p = .007), lower body power (p = .029) and agility (p = .003). In addition, the HIFT group decreased body fat (BF) %, while the TCT group increased BF% (p = .011). No changes were observed in aerobic or anaerobic capacity, flexibility, upper body power, or lower body stair climbing power. Newer, high intensity functional exercise programs such as HIFT may have better results on BC and similar effects when compared with TCT programs on health and fitness variables such as musculoskeletal strength and performance.
Victoria L. Goosey-Tolfrey
The purpose of this study was to examine the physiological changes in elite wheelchair basketball players leading up to the 2000 Paralympics. Twelve male players attended regular physiological assessments on six occasions; averaged data of two sessions for each year were used. Physiological measures included body mass, skinfold measurements, peak oxygen uptake and peak power obtained during maximal sprinting. VO2peak significantly increased from 2.65 to 2.83 L·min-1 prior to the Paralympics. Training had little influence on the anthropometric measurements or maximal sprinting data. In conclusion, the GB wheelchair basketball players appeared to have high levels of aerobic and anaerobic fitness. The longitudinal physiological profiles leading to the 2000 Paralympics suggest that players improved their aerobic base while maintaining other fitness prerequisites.
Richard D. Telford, Edward A. Catchpole, Vicki Deakin, Allan G. Hahn and Ashley W. Plank
The effect of vitamin and mineral supplementation was studied over 7 to 8 months of training and competition in 82 athletes from four sports: basketball, gymnastics, rowing, and swimming. Matched subgroups were formed and a double-blind design used, with subgroups being given either the supplementation or a placebo. All athletes were monitored to ensure that the recommended daily intakes (RDI) of vitamins and minerals were provided by diet alone. Sport-specific and some common tests of strength as well as aerobic and anaerobic fitness were performed. Coaches' assessment of improvement was also obtained. The only significant effect of supplementation was observed in the female basketball players, in which the supplementation was associated with increased body weight, skinfold sum, and jumping ability. A significant increase in skinfold sum was also demonstrated over the whole group as a result of supplementation. In general, however, this study provided little evidence of any effect of supplementation to athletic performance for athletes consuming the dietary RDIs.
Lothar Rokitzki, Enno Logemann, Georg Huber, Elfriede Keck and Josef Keul
This study was undertaken to evaluate the effects of 5 months of α-tocopherol supplementation on physical performance during aerobic exercise training in 30 top-class cyclists. Antioxidative effects of supplementation were also studied. Plasma α-tocopherol concentration increased significantly in the vitamin E-supplemented group, whereas the placebo group showed a trend toward decrease. Physical performance did not improve in the α-tocopherol-supplemented group compared to the placebo group. Heart rates were also not significantly different. Lactate concentrations at the aerobic threshold and the anaerobic threshold were identical. Thus, there was no performance improvement in the α-tocopherol-supplemented group. However there was a significant reduction in CK in serum of the E-supplemented group. A trend toward decrease in GOT, GPT, and LDH was observed with α-tocopherol supplementation. Moreover, significantly reduced malondialdehyde serum levels were measured in the E-supplemented group. The findings indicate a protective effect of α-tocopherol supplementation against oxidative stress induced by strenuous exercise.
James J. Hoffmann Jr, Jacob P. Reed, Keith Leiting, Chieh-Ying Chiang and Michael H. Stone
Due to the broad spectrum of physical characteristics necessary for success in field sports, numerous training modalities have been used develop physical preparedness. Sports like rugby, basketball, lacrosse, and others require athletes to be not only strong and powerful but also aerobically fit and able to recover from high-intensity intermittent exercise. This provides coaches and sport scientists with a complex range of variables to consider when developing training programs. This can often lead to confusion and the misuse of training modalities, particularly in the development of aerobic and anaerobic conditioning. This review outlines the benefits and general adaptations to 3 commonly used and effective conditioning methods: high-intensity interval training, repeated-sprint training, and small-sided games. The goals and outcomes of these training methods are discussed, and practical implementations strategies for coaches and sport scientists are provided.
Oleg Verbitsky, Joseph Mizrahi, Arkady Voloshin, July Treiger and Eli Isakov
The goal of this research was to analyze the effects of fatigue on the shock waves generated by foot strike. Twenty-two subjects were instrumented with an externally attached, lightweight accelerometer placed over the tibial tuberosity. The subjects ran on a treadmill for 30 min at a speed near their anaerobic threshold. Fatigue was established when the end-tidal CO2 pressure decreased. The results indicated that approximately half of the subjects reached the fatigue state toward the end of the test. Whenever fatigue occurred, the peak acceleration was found to increase. It was thus concluded that there is a clear association between fatigue and increased heel strike–induced shock waves. These results have a significant implication for the etiology of running injuries, since shock wave attenuation has been previously reported to play an important role in preventing such injuries.