Life Sciences Commons^™

Multiple Models Can Concurrently Explain Fatigue During Human Performance, C. Matthew Laurent†, Matt Green‡

International Journal of Exercise Science

One of the most commonly and thoroughly studied paradigms of human performance is fatigue. However, despite volumes of research there remains considerable controversy among scientists regarding definitive conclusions about the specific mechanism(s) contributing to fatigue. Within the literature there are three primary yet distinctly different governing ideas of fatigue; the traditionally referenced central model and peripheral model as well as the emerging central governor model (CGM). The CGM has recently been advocated by a limited number of researchers and is suggestive of a more integrative model of fatigue when compared the traditional peripheral and central models. However, more work is …

Determination Of Force Corresponding To Maximal Lactate Steady State In Tethered Swimming, Marcelo Papoti‡, Ricardo Vitório†, Sérgio A. Cunha†, Gustavo G. Araújo†, Adelino S.R. Silva‡, Vanessa Santhiago‡, Luiz E.B. Martins‡, Claudio A. Gobatto‡

International Journal of Exercise Science

The main aim of the present investigation was to verify if the aerobic capacity (AC) measured in tethered swimming corresponds to the maximal lactate steady state (MLSS) and its correlation with 30 min and 400m free style swimming. Twenty-five swimmers were submitted to an incremental tethered swimming test (ITS) with an initial load of 20N and increments of 10N each 3min. After each stage of 3min, the athletes had 30s of interval to blood sample collections that were used to measure blood lactate concentrations ([La-]). The ACBI was determined by the abrupt increase in [La-] versus force (F). The points …

The Short-Term Effect Of Whole Body Vibration Training On Sprint Start In Collegiate Athletes, Brad Roberts*, Iain Hunter‡, Ty Hopkins‡, Brent Feland‡

International Journal of Exercise Science

Whole body vibration (WBV) is characterized by a vibratory stimulus emitted throughout the body through the use of a vibrating platform on which the subject stands. Studies have shown over 30% increases in maximal explosive strength such as maximal speed biceps curl as well as increases in maximum dynamic force such as maximal sitting bench pull as the result of vibration. The purpose of this study was to investigate the effects of short term whole-body vibration on sprint starts among collegiate track athletes. On the first day eleven subjects were randomly assigned to either a non-vibration or vibration group for …

Evaluation Of Hand-To-Hand Bioelectrical Impedance Analysis For Estimating Percent Body Fat In Young Adults, Aaron M. Weaver*, Ashley C. Hill*, Joseph L. Andreacci‡, Curt B. Dixon‡

International Journal of Exercise Science

Purposes were to (a) to examine the validity and precision of a hand-to-hand bioelectrical impedance analyzer (HBIA) and (b) to determine the effect of an acute sub-maximal aerobic exercise bout on HBIA percent body fat (%BF) measures. Forty-one young adults (21 women; 20 men) visited the laboratory for body composition assessment on two separate occasions. During the control session, %BF was assessed by HBIA twice, before and immediately after 30 min of rest, and once by air-displacement plethysmography (ADP), using the BOD POD, which was considered the criterion method for comparison. During the exercise session, HBIA %BF measurements were determined …

A Kinematic And Kinetic Case Study Of A Netball Shoulder Pass, Sharon A. Hetherington*, Sibella G. King*, Denis Visentin‡, Marie-Louise Bird‡

International Journal of Exercise Science

The majority of studies analysing netball skills using force platforms have focused on reducing the risk of injury from compression and torsion forces on the knee and ankle joints during landing and pivoting. In this preliminary case study our aim was to investigate the efficacy of a combination of tools to describe the kinematic and kinetic mechanisms underlying the netball shoulder pass. The segmental movements of the netball shoulder pass were analysed from video and force platform data in order to develop a suitable methodology for use in a larger study. Peak vertical ground reaction force of 850 N was …

Psychosocial Correlates Of Physical Activity In Children And Adolescents In A Rural Community Setting, Kelly Crimi†, Larry D. Hensley‡, Kevin J. Finn‡

International Journal of Exercise Science

The purpose of this study was to evaluate the relationships between selected psychosocial factors and the physical activity behaviors of children (grade 4-8) and adolescents (grades 9-12) in a rural community setting. The Children’s Physical Activity Scale (CPAC)was used to measure the psychosocial factors of physical activity, The Physical Activity Questionnaire-Children (PAQ-C), and Physical Activity Questionnaire-Adolescents (PAQ-A) were used to measure the physical activity behaviors of the 167 participants. Results indicated that male and female physical activity behaviors were not significantly different. However, physical activity declined with age [F(8,147) = 5.44, p < 0.05, ES = 0.23]. All psychosocial factors were significantly correlated with physical activity in youth with the single highest correlation for males being “liking of exercise” (r = .61) and the highest correlation for females was “liking of games and sports”(r = .44). Stepwise regression analyses identified three subscales (liking of games and sport, liking of exercise, and parental support) in a significant prediction model of physical activity in both genders. The results indicate that children's physical activity is associated with a variety of psychosocial variables that represent import predisposing and reinforcing factors.

Balance Across Boundaries: Service Learning From An International Perspective, Teresa C. Fitts

International Journal of Exercise Science

Service-Learning provides students, faculty and community partners an opportunity to go beyond classroom and laboratory instruction to the application of theoretical principles, and the development of civic responsibility by forging meaningful relationships with community partners. Service-learning also enables faculty to broaden the cultural sensitivity and international exposure of students by engaging students in directed, purposeful projects aimed at supporting the goals of both the college and the international partners. We have a unique opportunity in Exercise Science to make lasting changes and improve global conditions relating to student learning and the physical inactivity crisis.

The purpose of this article is …

Comparison Of The Power Plate And Free Weight Exercises On Upper Body Muscle Endurance In Young Athletes, Elisabeth Boland*, Dan Boland*, Thomas Carroll‡, William R. Barfield‡

International Journal of Exercise Science

The power plate (PP) is designed to reduce training time while providing a muscle stimulus that leads to positive changes in muscle mass. This study investigated the effect that training on the PP has compared to a free-weight (FW) program, on upper body endurance, defined as the number of push-ups completed at one time prior to failure. Following IRB approval a pre-test was used to assess push-up endurance in PP and FW cohorts. Each group exercised for six consecutive weeks, working out three times per week, on non-consecutive days performing five exercises of two sets of 8-12 repetitions. Twenty-two females …

Predictors Of Adl Disability In Culturally Diverse Older Adults, Fernanda Winchester†, Rebecca Ellis‡, Maria Kosma‡, Katie E. Cherry‡, Priscilla D. Allen‡, Pamela A. Monroe‡, Robert H. Wood‡

International Journal of Exercise Science

The purpose of this study was to utilize the disablement pathway model to examine the contribution of physical function, dyspnea, and pain to disability in activities-of-daily-living (ADL) in culturally diverse older adults. Participants were 51 older adults (age = 69.0 years ± 9.7; 76.5% African-American, 51.0% < high school education, 52.9% < $20,000 annual income) from an urban community center and an independent living housing facility for seniors. Participants completed the Functional Status Index (FSI), which provides ratings of need for assistance (FSIA) and pain (FSIP) with ADL, the Continuous Scale Physical Functional Performance 10-item Test (CS-PFP10), and an analog dyspnea scale. Hierarchical multiple regression analyses revealed that facility, physical function, pain, and dyspnea accounted for 50.5% of the variance in disability and that pain (β = .43, p < .01) and physical function (β = -.39, p < .01) were the only significant predictors. In the second model, facility, dyspnea, and pain explained 27.6% of the variance in physical function, and facility (β = .39, p < .01) and dyspnea (β = -.26, p = .05) were the only significant predictors. Based on the disablement pathway model, physical functional improvement and pain prevention and management should be targeted when designing culturally appropriate strategies for delaying disability and maintaining independent life.

Consequences Of Weight Cycling: An Increase In Disease Risk?, Kelley Strohacker†, Katie C. Carpenter†, Brian K. Mcfarlin‡

International Journal of Exercise Science

Research indicates that weight cycling, or “yo-yo dieting” is a common occurrence in obese populations. The long term negative health consequences of weight cycling are debated and it is unclear whether or not this weight change pattern poses a greater disease risk compared to obesity maintenance. This review discusses the prevalence of weight cycling and physiological alterations occurring during weight loss that promotes weight regain. We also discuss the effect weight regain has upon adipose tissue in terms of rate and type of accumulation. Also within this review are discussions surrounding the previously published literature based upon human and rodent …

The Effects Of Tempur Insoles On Ground Reaction Forces And Loading Rates In Running, Crystal Ruano*, Douglas Powell‡, Elizabeth T. Chalambaga*, Doug Renshaw*

International Journal of Exercise Science

Runners often experience over-use injuries. Ground reaction force (GRFs) patterns have been associated with these over-use injuries; however, it is not solely the magnitude of GRFs, but also the rate at which they are applied that lead to lower extremity injury. Many recreational runners will use over-the-counter insoles as a method of treating or preventing injury. Therefore, the purpose of this study was to examine the efficacy of two insoles on peak GRFs and loading rates. It was hypothesized that no differences in peak GRFs or loading rates would exist with the addition of two insoles during running. Twelve subjects …

Physical Activity Is Associated With Percent Body Fat And Body Composition But Not Bmi In White And Black College Students, Michael Zanovec†, Anantha P. Lakkakula†, Lisa G. Johnson‡, Georgianna Tuuri‡

International Journal of Exercise Science

The objective of this study was to examine the association of self-reported physical activity (PA) with body composition in 290 college students (49% male, 60% White) 18-25 years of age. Outcome measures included: self-reported PA levels calculated in MET-hrs·wk-1 from the International Physical Activity Questionnaire (IPAQ); body mass index (BMI; in kg·m-2); and body composition variables estimated by dual-energy X-ray absorptiometry (DXA). Mean activity levels of the sample were 39.8 ± 23.8 MET-hrs·wk-1. Participants were divided into quartiles of PA levels: ≥0 to <24.0, ≥24.0 to <34.0, ≥34.0 to <51.25, and ≥51.25 MET-hrs·wk-1 and body composition variables were compared by group. Chi-square analyses revealed a significant difference for gender by PA quartile [χ2 (3, N=290) = 32.42, p < 0.0001], and for gender by race by PA quartile [χ2 (9, N=290) = 37.82, p < 0.0001]. MET-hrs·wk-1 was inversely correlated with %BF (r = -0.40, p < 0.0001) but not BMI (r = 0.05, p = 0.43). When comparing body composition variables across PA quartiles, no significant differences were observed for BMI; however, subjects in the highest quartile of PA had a lower percent body fat (%BF) and fat mass (FM), and a higher lean-tissue mass (LTM) compared to subjects in the other three groups. In this cohort of young adults, participants in the highest activity group had a more fit body composition profile (e.g., lower %BF, lower FM, and higher LTM) which was not reflected in BMI and was independent of gender and race.

Active Video/Arcade Games (Exergaming) And Energy Expenditure In College Students., Shannon R. Siegel‡, Bryan L. Haddock‡, Andrea M. Dubois*, Linda D. Wilkin‡

International Journal of Exercise Science

Video games have become increasingly popular among young adults. The purpose of this pilot study was to determine if interactive video/arcade games, requiring physical activity to play, increase the energy expenditure (EE) and heart rate (HR) of young adults enough to elicit a training response. Thirteen male and female participants 26.6 ± 5.7 years of age were in the study. Participants were familiarized with equipment and allowed to practice with three games: (1) moving and striking lighted pads, (2) riding a bike to increase the pace of a race car, and (3) boxing against a video simulated opponent. A portable …

Academic And Research Programs In Exercise Science, South Korea, Kyung-Shin Park, Wook Song

International Journal of Exercise Science

We appreciate the opportunity to review academic curriculum and current research focus of Exercise Science programs in South Korea. The information of this paper was collected by several different methods, including e-mail and phone interviews, and a discussion with Korean professors who attended the 2009 ACSM annual conference. It was agreed that exercise science programming in South Korea has improved over the last 60 years since being implemented. One of distinguishable achievement is that exercise science programs after the 1980’s has been expanded to several different directions. It does not only produce physical education teachers but also attributes more to …

Exercise Science Academic Programs And Research In Brazil, Roberto Simão, Jonato Prestes

International Journal of Exercise Science

The International Journal of Exercise Science has enjoyed an association with several students and professionals from Brazil. In this invited editorial, professors from leading institutions in Brazil, Roberto Simão from Rio de Janeiro Federal University, and Jonato Prestes from the Federal University of São Carlos, share information regarding their programs relating to Exercise Science. They have provided information on academic components such as entrance requirements, progression through programs, and professional opportunities available to students following completion; as well as details regarding funding available to students to participate in research, collaboration, and specific research interests.

Power Training: Can It Improve Functional Performance In Older Adults? A Systematic Review, John Rice†, Justin Keogh‡

International Journal of Exercise Science

Older adults’ reduced performance in functional activities of daily living (ADL) such as gait, sit to stand or stair climbing may reflect age-related declines in muscular power more so than strength. Therefore, this review was conducted to determine if power training is effective in improving the functional ability of older adults, and if so, if it was more effective than strength training. The review was performed using Medline (PubMed), CINAHL, Sports Discus, ProQuest 5000 International and Google Scholar with the keywords “power training”, “older adult” and “elder” and all derivatives. Of the 12 eligible studies identified, nine also included a …

Determination Of Systolic Blood Pressure Recovery Time After Exercise In Apparently Healthy, Normotensive, Non-Athletic Adults And The Effects Of Age, Gender, And Exercise Intensity, Uchechukwu Dimkpa†, Andrew C. Ugwu‡

International Journal of Exercise Science

The aim of this study was to determine in statistical terms, the systolic blood pressure recovery time (SBPRT) and the effects of age, gender and exercise intensity in a large sample of apparently healthy non-athletic adults (n=597, aged 18-68). Subjects performed mild, moderate, and severe ergometer exercise tests. Blood pressure was measured before exercise (after 10 and 15 minutes of rest), during exercise (at 2-minute intervals) and at every minute of post-exercise recovery until systolic blood pressure (SBP) returned to baseline. The present findings indicate that the average values of SBPRT were between 5 and 7 minutes regardless of age, …

Anthropometric And Physiological Predictors Of Flat-Water 1000 M Kayak Performance In Young Adolescents And The Effectiveness Of A High Volume Training Camp., Scott C. Forbes†, Daniel L. Fuller†, Joel R. Krentz†, Jonathon P. Little†, Phillip D. Chilibeck‡

International Journal of Exercise Science

Our purpose was to determine the relationship of anthropometric and physiological variables with 1000m flat-water kayak (K1000) performance. A secondary purpose was to determine the effectiveness of a high volume training camp. High performance young adolescent kayakers (n=13, 8 males, 5 females, 15±1 yrs) participated in this study. Testing before and after the 3-4 week training camp included anthropometric measurements (height, sitting height, arm span, and body mass), strength (1-RM: bench press and bench pull), flexibility (sit and reach), and an incremental kayak ergometer test to determine peak oxygen uptake (VO2peak) and anaerobic threshold, and an open water K1000 time …

The Influence Of An Environmental Cue And Exercise On Food Consumption In College Students, Samantha J. Hackbart †, James D. Lecheminant‡, John D. Smith‡, Curt L. Lox‡

International Journal of Exercise Science

The purpose of this study was to determine the effect of an environmental cue (bowl size) on food consumption and to examine the influence of exercise on that relationship. This cross-sectional study included 286 college students attending a large Midwestern University. Upon arrival at an ice cream social for university students, participants were randomly given a small (8 oz) or large (12 oz) bowl and a 4-page survey addressing exercise and eating habits. At the social, participants were invited to dish themselves as much ice cream as they wanted and the amount consumed was determined by weighing the bowl with …

Determination Of Blood Lactate Concentration: Reliability And Validity Of A Lactate Oxidase-Based Method, Rachel White*, Daniel Yaeger*, Stasinos Stavrianeas‡

International Journal of Exercise Science

The measurement of blood lactate has long been used as marker of exercise intensity and training status. We compared a commercially available lactate oxidase spectrophotometric method (LO) to determine blood lactate levels to two previously validated methods, the lactate dehydrogenase spectrophotometric method (LDH), and the YSI 1500L Sport lactate analyzer (YSI). First we established a series of calibration curves over physiological range of lactate values (1-15 mM∙l-1 for the spectrophotometric assays and 1-30 mM∙l-1 for the YSI) with high correlations (0.986 < r < 0.999). Aerobically trained participants (n = 11) performed repeated exercise bouts of varying intensities on a cycle ergometer. Capillary blood samples (n = 189) were collected from the earlobe and the blood lactate concentration was determined using each of the three methods. An ANOVA (alpha=0.05) revealed no differences in blood lactate concentrations between the three methods. The three experimental protocols yielded similarly-shaped lactate curves, although the actual values for the LDH method was somewhat lower than the LO and the YSI at every intensity level. Bland-Altman plots revealed a slight bias towards lower lactate values with the LDH method, perhaps indicative of a more conservative measure of blood lactate. We conclude that the LO method is a reliable and valid method to determine blood lactate concentrations spectrophotometrically. All three methods can provide useful within-subject lactate curves, although we caution against interchangeable use of the three methods.

Spatting Restricts Ankle Motion More Effectively Than Taping During Exercise, Brian E. Udermann†, Kevin C. Miller†, Scott T. Doberstein‡, David M. Reineke‡, Steven R. Murray‡, Robert W. Pettitt‡

International Journal of Exercise Science

Ankle injuries, via plantarflexion (PF) and inversion, are commonplace today. To reduce ankle injuries, restrictive appliances such as taping and bracing have been employed. These appliances, however, have the disadvantage of potentially loosening considerably with mild activity. Spatting—applying tape over the shoe and sock—has been suggested as a viable alternative, yet its efficacy has not been researched widely. We examined the effects of taping or spatting the ankles on 17 men (age = 20.7 ± 2.1 years; height = 185.7 ± 5.7 cm; mass = 93.6 ± 16.2 kg) before, during, and after 60 minutes of exercise involving multi-directional activity. …

Validation Of The Actiheart Monitor For The Measurement Of Physical Activity, Tiago V. Barreira†, Minsoo Kang‡, Jennifer L. Caputo‡, Richard S. Farley‡, Matthew S. Renfrow†

International Journal of Exercise Science

The Actiheart monitor uniquely allows simultaneous measurement of heart rate and movement counts. The purpose of this study was to establish validity evidence for the Actiheart monitor under laboratory and free-living conditions. A total of 34 college students (17 males and 17 females, age = 21.8 ± 3.6 years) participated in the study. In the laboratory environment, the participants completed three, 5 min bouts of treadmill walking and/or running at speeds of 3.2, 6.4, and 9.6 km/h. Outside the laboratory, participants were asked to perform free-living physical activity for 30 min. For validation, energy expenditure, movement counts, and heart rate …

Modeling Oxygen Uptake During V1 Treadmill Roller Skiing, Robert S. Bowen†, Randall L. Jensen‡, Jennifer M. Ryan†, Phillip B. Watts‡

International Journal of Exercise Science

The use of regression equations to predict oxygen uptake in relation to speed, grade, power output, and anthropometric characteristics is common in cardiac rehabilitation and athlete fitness testing. Research has suggested that sport specific testing improves the reliability of the test methodology and is appropriate for the development of effective training programs. This study focused on the development of a cross-country skiing specific predictor of maximal oxygen uptake based on treadmill speed, treadmill grade, gender, and body mass. This project simulated snow skiing on a large research treadmill using roller skis. A small sample size (N = 34) warranted the …

Exercise Bouts At Three Different Intensities Fail To Potentiate Concentric Power, Chad A. Cabrera†, Jacobo Morales‡, Felicia Greer‡, Robert W. Pettitt‡

International Journal of Exercise Science

Postactivation potentiation (PAP) has been hypothesized previously to occur during voluntary, concentric actions. We tested the hypothesis that one of at least three different intensities of conditioning exercises would evoke potentiation of power during the concentric, bench press throw (BPT). Twelve men (age = 22.9 &#; 2.7 years, bench press 1 repetition maximum (1RM) = 1.20 ± 0.12 kg•kg-1 body weight) completed five isotonic conditioning presses at ~55, 70, and 86% 1RM, in counterbalanced order, and on separate days. Average and peak power of the BPT using a load of 55% 1RM along with surface electromyography (EMG) of the triceps …

Influence Of Body Composition, Oral Contraceptive Use, And Physical Activity On Bone Mineral Density In Premenopausal Women, Vanessa D. Sherk†, Clint D. Howard†, Michael G. Bemben‡, Debra A. Bemben‡

International Journal of Exercise Science

In premenopausal women, low bone density may reflect attainment of a lower peak bone mass which can increase risk of osteoporosis after menopause. The purpose of this study was to examine the relationship between total body, lumbar spine, and proximal femur bone mineral density (BMD) and body composition and oral contraceptive (OC) use in 18-30 year old women. Sixty-five healthy women, split into groups of oral contraceptive users (OC, n = 36) and non oral contraceptive users (Non-OC, n = 29), completed Baecke physical activity, calcium intake, and menstrual history questionnaires. Total body, AP lumbar spine, and dual proximal femur …

Comparison Of Body Composition Measurements Using A New Caliper, Two Established Calipers, Hydrostatic Weighing, And Bodpod, Erin E. Talbert*, Michael G. Flynn‡, Jeffrey W. Bell†, Andres E. Carrillo†, Marquita D. Dill†, Christiania N. Christensen*, Colleen M. Thompson†

International Journal of Exercise Science

Purposes: (1) To compare the Lafayette Instruments (LI) skinfold caliper to the Lange (L) and Harpenden (H) calipers using a diverse subject population. (2) To determine the validity of the LI caliper in a subset of subjects by comparing body compositions from skinfold thicknesses to those measured by hydrostatic weighing (HW) and air displacement plethysmography (ADP). (3) To compare measurements obtained by experienced (EX) and inexperienced (IX) technicians using all three calipers. Methods: Skinfold measurements were performed by both EX and IX technicians using three different calipers on 21 younger (21.2 ± 1.5 yrs) and 20 older (59.2 ± 4 …

Timing Carbohydrate Beverage Intake During Prolonged Moderate Intensity Exercise Does Not Affect Cycling Performance, George G. Schweitzer†, John D. Smith‡, James D. Lecheminant‡

International Journal of Exercise Science

Carbohydrate beverages consumed during long-term exercise have been shown to attenuate fatigue and improve performance; however, the optimal timing of ingestion is unclear. Therefore, the purpose of this study was to determine if timing the carbohydrate ingestion (front-loading (FL), continual loading (CL), and end-loading (EL)) during prolonged exercise influenced exercise performance in competitive cyclists. Ten well-trained cyclists completed three separate exercise bouts on a bicycle ergometer, each lasting 2 hours at an intensity of ~67% VO₂ max, followed by a 15-minute “all out” time trial. In the FL trial, participants ingested a carbohydrate beverage during the first hour and …

From The Editors: Assessing The International Journal Of Exercise Science After One Year, T. Scott Lyons, James W. Navalta

International Journal of Exercise Science

Western Kentucky University (WKU) strives to be a “leading American university with international reach.” In an effort to contribute to that mission, Drs. Scott Lyons and James Navalta of the Exercise Science program endeavored in 2007 to start a student-focused, on-line journal. Working closely with Berkeley Press, the platform for the International Journal of Exercise Science (IJES) was established during the summer of 2007 and it went “live” in January 2008. The journal has now been on-line for over one year and has enjoyed great success, with quality research submitted from graduate and undergraduate students, as well as professionals. We …