Background and Purpose—There is controversy in the literature regarding the relationship between intima-media thickness (IMT) and body composition among adolescents. This study investigated the relationship between body fat percentage and IMT, while controlling for height, weight, age, blood pressure, cholesterol, glucose, triglycerides and VO2max in 12 to 17-year-old children. Methods—111 children (mean age = 14.33 years) participated in this study. Body fat percentage was assessed using dual energy x-ray absorptiometry (DXA). A B-mode, high-resolution ultrasonograph was used to measure the IMT of the right and left common carotid arteries (CCA). Fasting blood tests were performed to obtain blood lipid and glucose profiles. Blood pressure was measured using an automatic blood pressure cuff.Results—Data were divided into body fat tertiles to compare differences between the upper and lower tertile. Contrary to what might be expected, the mean IMT of the group with the lowest body fat percent was 0.516 mm and the mean IMT for the upper tertile of body fat percent was 0.483 mm (F(2,103) = 5.883, p = 0.004). Post hoc analysis indicated that the two leanest groups had significantly thicker IMT than the group with the highest percent body fat (p = 0.005 and p = 0.027, respectively). The two leanest groups were not significantly different from each other. When controlling for gender, no significant relationship existed between CCA-IMT and body fat percentage (F(2,103) = 2.267, p = 0.109). Conclusions—This study found that there were significant differences in IMT between body fat percentage and CCA-IMT in children and adolescents 12 to 17-years of age. This study did indicate that as body fat increases, risk factors such as cholesterol and triglycerides also increase. Overall, the direct relationship between CCA-IMT and body fat percentage is poorly understood in children and adolescents. Further research is necessary to determine a standardized protocol for assessing atherosclerotic risk in adolescents.

Abstract This study sought to develop an interval prone bridge fitness test to assess core stabilization in healthy adults (ages 18–39 years). Participants performed a prone bridge maneuver in alternating 15-sec work and 5-sec rest intervals with participants' RPE scores (0–10) recorded at the end of each work interval. The RPE score reported after 95 sec (RPE-95) was used to predict total interval prone bridge endurance time along with participants' self-reported level of physical activity (PA; sedentary = 0, low active = 1, active = 2, very active = 3). Multiple linear regression was employed to generate the following prediction equation (R = .86, SEE = 32.98 sec): Total time (sec) = 300.0 – (23.4 x RPE-95) + (17.7 x PA). Each predictor variable was statistically significant (RPE-95, p < .0001; PA, p = 0.006) and cross validation procedures using PRESS (predicted residual sum of squares) statistics revealed minimal shrinkage (Rp = .85 and SEEp = 32.89 sec). The mean and standard deviation (±SD) for the total duration of the interval prone bridge test and the RPE-95 data were 179.9 ± 65.2 sec and 6.3 ± 2.2, respectively. To assess test-retest reliability, a second test was completed about 48 hours after the first. The reliability study (n = 45) yielded an acceptable test-retest intraclass reliability coefficient (ICC = .95, SEM = 12.7 sec) when comparing total interval prone bridge endurance times across days. In summary, this interval prone bridge fitness test, and accompanying regression model, yields a relatively accurate estimate of total interval prone bridge test time in healthy men and women, using both RPE-95 and PA data.

Introduction: Very few studies have looked at the effect of vibration on flexibility, and no studies exist that have looked at stretching concurrently with whole body vibration (WBV) training. Therefore, the purpose of this study was to determine if whole-body-vibration training (WBV) done concurrently with static stretch (SV) is more effective than static stretching alone (SS), and to see if WBV training independently (SQ) improves hamstring flexibility without stretching. A secondary purpose of this study is to determine if retention of flexibility gains are maintained. Methods: Forty-four subjects (31 men, 13 women) completed this study (age 22.5 ± 1.8 years; body mass 75.54 ± 13.18 kg; height 176.7 ± 8.06 kg). All subjects were randomly assigned to 1 of 5 groups: SV group (8 males, 3 females), SQ group (8 m, 4 f), SS group (8 m, 3 f), and the C group (7 m, 3 f). All subjects were measured bilaterally for hamstring flexibility using the lying passive knee extension test (LPKE) prior to group assignment. Subjects from each treatment group reported to lab 5 times per week for treatment. Subjects stood on the WBV platform for 5 repetitions of 30-seconds at with 30-seconds in between bouts. The SV group stretched hamstrings while standing on the WBV during the vibration bouts (at 26 Hz and 4 mm amplitude). The SS group did the same thing except the unit was not turned on. The SQ group stood on the WBV platform in a semi-squat position similar to most WBV training studies, without stretching, but with vibration. The C group stood on the WBV platform in a semi-squat without vibration. Analysis and Results: A mixed models analysis of covariance (ANCOVA) was used while blocking on subjects to analyze data using the statistical program SAS (version 9.1). A Bonferroni correction was used for significance on all post hoc tests (p<.0001). At baseline there were no significant differences between groups for flexibility (see Table 1), showing that each group was similar in flexibility to start. Throughout the treatment period (3 weeks of stretching) both the SS and SV groups had significant increases in flexibility compared to SQ and C. Analysis of the slopes (rate of change) for the treatment period was significantly different between the SV group and all other groups (p<.0001 for all comparisons), showing that the SV group had a greater rate of change than all other groups. For the retention period there was no significant difference between the SV and SS group (p=0.0455), but there was a significant difference between both the SV and SS groups and all other groups (p<.0001 for all comparisons). Conclusion: Stretching during WBV improves flexibility more than static stretching alone and at a faster rate. WBV on its own without stretching does not significantly improve hamstring flexibility.

The purpose of this study was to develop a multiple linear regression model to predict treadmill VO2max scores using both exercise and nonexercise data. One hundred five college-aged participants (53 male, 52 female, mean age 23.5 ± 2.8 yrs) successfully completed a submaximal cycle ergometer test and a maximal graded exercise test (GXT) on a motorized treadmill. The submaximal cycle protocol required participants to achieve a steady-state heart rate (HR) equal to at least 70% of age-predicted maximum HR (220-age), while the maximal treadmill GXT required participants to exercise to volitional fatigue. Relevant submaximal cycle ergometer test data included a mean (± SD) ending steady-state HR and ending workrate equal to 164.2 ± 13.0 and 115.3 ± 27.0, respectively. Relevant nonexercise data included a mean (± SD) body mass (kg), perceived functional ability [PFA] score, and physical activity rating [PA-R] score of 74.2 ± 15.1, 15.7 ± 4.3, and 4.7 ± 2.1, respectively. Multiple linear regression was used to generate the following prediction of cardiorespiratory fitness (R = 0.91, SEE = 3.36 ml∙kg-¹∙min-¹): VO2max = 54.513 + 9.752 (gender, 1 = male, 0 = female) − 0.297 (body mass, kg) + 0.739 (PFA, 2-26) + 0.077 (work rate, watts) − 0.072 (steady-state HR). Each predictor variable was statistically significant (p < .05) with beta weights for gender, body mass, PFA, exercise workrate, and steady-state HR equal to 0.594, -0.544, 0.388, 0.305, and -0.116, respectively. The predicted residual sums of squares (PRESS) statistics reflected minimal shrinkage (RPRESS = 0.90, SEEPRESS = 3.56 ml∙kg-¹∙min-¹) for the multiple linear regression model. In summary, the submaximal cycle ergometer protocol and accompanying prediction model yield relatively accurate VO2max estimates in healthy college-aged participants using both exercise and nonexercise data.

The purpose of this study was to determine the validity and reliability of four methods of estimating body composition in 331 participants (177 boys, 154 girls) between 12-17 years of age. Percent body fat (%BF) was assessed once on one day using DEXA and twice using the sum of two skinfold (SF) and three bio-electrical impedance analysis (BIA) devices: OMRON hand-to-hand BIA, TANITA 521 foot-to-foot BIA, and TANITA 300A foot-to-foot BIA. The same assessments were repeated on 79 of the participants on a second day. DEXA was used as the criterion method of estimating %BF. The agreement between the estimates of %BF from the sum of two SF and the three BIA devices and DEXA was evaluated using linear regression and Bland-Altman analyses. Although the two analyses generally led to similar conclusions about each of the four prediction methods, the specific interpretations of each analysis varied because of the inherent differences in the analyses. In an attempt to determine if any of the four prediction methods were interchangeable with DEXA, the 95% confidence interval (CI) and prediction interval (PI) around the line-of-best-fit through the data are reported. The results of this study indicate that (a) all of the methods used in this study to estimate %BF were reliable within and between days, (b) the TANITA 300 BIA device performed poorly in both boys and girls and should not be used to assess body composition in children and adolescents, (c) none of the four prediction methods performed well in both boys and girls across the entire range of %BF values of the subjects in this study, (d) the sum of two SF, OMRON and TANITA 521 are acceptable for use in large population-based studies but are not recommended when the accurate assessment of body composition of an individual is critical, in which case (e) criterion methods of assessing body composition should be used.

The purpose of this study was to evaluate increased cardiac output (Q) on oxygen kinetics at exercise intensities above and below the lactate threshold (LT). We hypothesized the increase in Q using head-out water immersion (HOI) while treadmill running would reduce the rate constant of the fast component and reduce the amplitude of the slow component of oxygen kinetics compared with land treadmill running. Subjects (n=10) performed two 6 min exercise bouts at a 15% below and above the LT on a land and underwater treadmill following rest. A single exponential equation [VO2(t) = VO2(b) + A1•(1-e-t/TC1] was used to evaluate VO2. The slow component at the end of exercise was estimated by subtracting (VO2(b) + A1) from the plateau. The mean LT for HOI running 1.80 ± .09 L • min-1 was significantly lower (p < 0.05) than 2.15 ± 1.03 L • min-1 while running on the land. The Q during HOI exercise below and above the LT (16.5 ± 0.6 L • min-1, 18.0 ± 1.2 L • min-1) was significantly higher (p < 0.05) than the Q during exercise below and above the LT on land (11.5 ± 0.8 L • min-1, 13.0 ± 0.7 L • min-1). During HOI exercise below LT time to reach steady-state was delayed (8 ± 2 s). Exercise above LT showed similar phase one time constants for all exercise trials. The amplitude of the slow component was not influenced by HOI. As such, the increase in during HOI exercise did not hastening uptake kinetics.

Context: It is common practice to treat musculoskeletal injury acutely with cryotherapy with compression. A tobacco poultice and the SportsWrap are touted as effective acute care treatments, yet are unproven. Objective: Compare four treatments (cryotherapy with compression, compression alone, a tobacco poultice, and the SportsWrap) of an experimentally induced bruise to determine their effectiveness at limiting bruise formation, thereby decreasing overall bruise duration. Design: Randomized, controlled, blinded trial. Setting: Research laboratory. Participants: 64 male participants (height: 180.2±6.4cm, weight: 78.0±16.2kg, age: 22.1±2.8yrs) volunteered. Participants committed to not exercise during participation and were free of medication affecting coagulation or inflammation at least 3 days before and throughout the study. Interventions: Participants were shot in both quadriceps with a tennis ball fired from a tennis ball machine at ~31m/sec from 46cm. Digital pictures were taken of the trauma site immediately before and on days 2, 4, 6, 8, and 10 post-trauma. Within 5 minutes of being shot, participants were randomly assigned to receive 1 of 4 treatments to one of their legs: 1) cryotherapy with compression (applied 5 times separated by 2 hours, compression applied with and without the ice until return on Day 2); 2) compression alone (worn continuously until Day 2); 3) a tobacco poultice (worn for no less than 12 hours, then removed; compression reapplied until Day 2); and 4) the SportsWrap (worn continuously until Day 2). Treatment times reflected clinical practice. Untreated leg served as control. Two raters, blinded to treatment and treatment leg, analyzed each bruise, while a third analyzed an unbruised control area for normalization. Software calculated average pixel values of cyan, magenta, yellow, black, and luminosity for each picture. This analysis was shown to be reliable during pilot data collection (ICC = .77) and has been used previously. Main Outcome Measures: Color difference, a unitless value, was calculated as the difference between the treatment and control legs from the normalized average pixel values. A 2 x 4 x 6 mixed model ANOVA followed by Bonferroni post hoc analysis determined differences between limbs and treatments over time. Results: There was no treatment (F3,60 = .47, P = .70) or limb (F1,60 = .04, P = .84) effect, but there was a day effect (F3.9,234.5 = 6.82, P < .001). The mean color difference values were greater on Days 4 and 6 than Days 0 and 10, and Day 4 was greater than Day 2 (Bonferroni < .05). None of the interactions were significant. Conclusions: Treatment had no effect on the degree of bruising that we produced in this study. We are reluctant to generalize this data to musculoskeletal injury beyond what we caused because of insufficient bruising/too great of variance in bruising.

The purposes of this study were to evaluate the effects touches per play, post touches per play, and dribbles to end a play (DEP) have on points per play, field goal percentage, turnovers, and fouls. This was done to provide empirical evidence on anecdotal theories held by coaches concerning ball movement, dribbles, and post touches. The data collected were statistically analyzed using Bayesian hierarchical models. This study reports some intriguing trends. First, exceeding nine passes and three dribbles to end a play results in a decrease in points per play and field goal percentage. Second, up to three dribbles into a shot was more productive and efficient than shooting with no dribbles. Third, post play does not have as big an effect on offensive basketball as previously expected. Lastly, offensive rebounds seem to universally have a positive effect upon offensive basketball. This study supported some anecdotal beliefs about basketball, while not others, supporting the idea for statistically based studies to be conducted on anecdotal beliefs held about basketball.

Yoga adherents claim many benefits of the practice, including promotion of bone health and prevention of osteoporosis. However, few, if any, studies have investigated whether yoga enhances bone mineral density. Furthermore, none have identified force generation in yoga. The purpose of this study is to collect ground reaction force (GRF) data on a variety of common hatha yoga postures that would be practiced in fitness centers or private studios. Twelve female and eight male volunteers performed a sequence of 28 common hatha yoga postures while ground reaction force data were collected with an AMTI strain-gauge force plate. The sequence was repeated six times. Four variables were studied: the maximum vertical GRF, the mean vertical GRF, the maximum resultant GRF, and the mean resultant GRF. Univariate analysis was used to identify mean values and standard deviations for each of the four variables. Multivariate analysis revealed some variation due to gender but none due to age or weight. Means were similar across all poses and subjects, and standard deviations were small. This unique yoga sequence produced low impact forces in both upper and lower extremities. Further research is warranted to determine whether these forces are sufficient to promote osteogenesis or maintain current bone health in yoga practitioners.

The prevalence of physical inactivity has been recognized as a risk factor for multiple chronic disease conditions in both adults and children. Recently efforts to increase healthy behaviors have been promoted through religious groups (Ken Resnicow et al., 2002). The Church of Jesus Christ of Latter-day Saints (LDS) has a unique program called Family Home Evening (FHE) that could be used to teach and potentially improve physical activity. Six FHE lessons were designed to be taught in 6 consecutive weeks within a family environment. A total of 84 families (parents and children) were recruited for participation. Participating families were randomized into either the control or intervention group. All family members were given pedometers to be worn one week prior to, and one week after the 6-week intervention. The intervention group FHE lessons covered physical activity promoting topics, and the control group was given traditional religious topics for their FHE lessons. ANOVA indicated that in children there was an increase in daily steps in the intervention group (12482.8 SD=4455.3) compared to the control group (11255.4 SD=4048.9), which was statistically significant (F (1,85) = 3.93, p=.05). In adults there was an increase in steps in the intervention group from pre to posttest of 8823.5 (SD=3858.3) to 9947.4 (SD=4222.8) this difference was statistically significant (t = -2.94, p<.01). There was no significant change in pedometer steps for the control group in either adults or children. Results of this study suggest that FHE may be a useful mechanism for increasing steps taken daily. There are other factors that may increase the effectiveness of the lessons such as readiness of the participants to change, number of lessons, lesson content and/or time between lessons.