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Raoul F. Reiser II, Michael L. Peterson and Jeffrey P. Broker

While the recumbent cycling position has become common for high-performance human-powered vehicles, questions still remain as to the influence of familiarity on recumbent cycling, the optimal riding position, and how recumbent cycling positions compare to the standard cycling position (SCP). Eight recumbent-familiar cyclists and 10 recreational control cyclists were compared using the 30-s Wingate test in 5 recumbent positions as well as the SCP. For the recumbent positions, hip position was maintained 15° below the bottom bracket while the backrest was altered to investigate body configuration angle (BCA: the angle between the bottom bracket, hip, and a marker at mid-torso) changes from 100° to 140° in 10° increments. Between-groups analysis found that only 4 of the 126 analyzed parameters differed significantly, with all trends in the same direction. Therefore both groups were combined for further analysis. Whole-group peak power (14.6 W/kg body mass) and average power (9.9 and 9.8 W/kg body mass, respectively) were greatest in the 130° and 140° BCA positions, with power dropping off as BCA decreased through 100° (peak = 12.4 W/kg body mass; avg. = 9.0 W/kg body mass). Power output in the SCP (peak = 14.6 W/kg body mass; avg. = 9.7 W/kg body mass) was similar to that produced in the 130° and 140° recumbent BCA. Average hip and ankle angles increased (became more extended/ plantar-flexed), 36° and 10°, respectively, with recumbent BCA, while knee angles remained constant. The lower extremity kinematics of the 130° and 140° BCA were most similar to those of the SCP. However, SCP hip and knee joints were slightly extended and the ankle joint was slightly plantar-flexed compared to these two recumbent positions, even though the BCA of the SCP was not significantly different. These findings suggest: (a) the amount of recumbent familiarity in this study did not produce changes in power output or kinematics; (b) BCA is a major determinant of power output; and (c) recumbent-position anaerobic power output matches that of the SCP when BCA is maintained, even though lower extremity kinematics may be altered.

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Bareket Falk and Oded Bar-Or

A mixed cross-sectional longitudinal design was used to study the effect of growth and physical maturation on peak aerobic and anaerobic mechanical power. Subjects were divided into three groups based on Tanner staging: 16 prepubertal (PP, Stage 1), 15 midpubertal (MP, Stages 2, 3, 4), and 5 late pubertal (LP, Stage 5). Aerobic and anaerobic power were observed every 6 months for IS months. Peak mechanical aerobic power and peak oxygen consumption were determined using a progressive cycle ergometer test. Anaerobic power indices were derived from the Wingate Anaerobic Test. There was no difference in peak mechanical aerobic power (in W · kg−1) among the maturation groups, nor with chronological age. There was a significant difference in peak and mean anaerobic power (in W · kg−1) among maturation groups, but the increase with chronological age was not statistically significant. There was a significant correlation between aerobic and anaerobic power (in Watt) during each session among the PP and MP boys but not among the LP boys. This may suggest that the child’s metabolic specialization into either an aerobic or anaerobic performer begins in late puberty.

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C. Kerksick, C. Rasmussen, R. Bowden, B. Leutholtz, T. Harvey, C. Earnest, M. Greenwood, A. Almada and R. Kreider

This study examined whether ribose supplementation before and during intense anaerobic exercise impacts anaerobic capacity and metabolic markers. Twelve moderately trained male cyclists (22.3 ± 2.2 y; 181 ± 6 cm, 74.8 ± 9 kg) participated in the study. Subjects were familiarized and fasted for 8 h after standardizing nutritional intake. In a double blind and crossover manner subjects ingested either a 150 mL placebo or ribose (3 g ribose + 150 μg folate). Subjects rested for 25 min and completed 5 × 30 s anaerobic capacity tests with 3 min passive rest. Six capillary blood samples were taken prior to and after sprints for adenine nucleotide breakdown determination. The experiment was repeated 1 wk later with alternative drink. Data were analyzed by repeated measures ANOVA. No significant interactions were observed for any performance or blood variables. D-ribose supplementation has no impact on anaerobic exercise capacity and metabolic markers after high-intensity cycling exercise.

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Webb A. Smith, Andrew C. Fry, Lesley C. Tschume and Richard J. Bloomer

The purpose of this study was to evaluate the effect of glycine propionyl-Lcarnitine (GPLC) supplementation and endurance training for 8 wk on aerobicand anaerobic-exercise performance in healthy men and women (age 18–44 yr). Participants were randomly assigned to 1 of 3 groups: placebo (n = 9), 1 g/d GPLC (n = 11), or 3 g/d GPLC (n = 12), in a double-blind fashion. Muscle carnitine (vastus lateralis), VO2peak, exercise time to fatigue, anaerobic threshold, anaerobic power, and total work were measured at baseline and after an 8-wk aerobic-training program. There were no statistical differences (p > .05) between or within the 3 groups for any performance-related variable or muscle carnitine concentrations after 8 wk of supplementation and training. These results suggest that up to 3 g/d GPLC for 8 wk in conjunction with aerobic-exercise training is ineffective for increasing muscle carnitine content and has no significant effects on aerobic- or anaerobic-exercise performance.

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Kerry McGawley, Erwan Leclair, Jeanne Dekerle, Helen Carter and Craig A. Williams

The Wingate cycle test (WAnT) is a 30-s test commonly used to estimate anaerobic work capacity (AWC). However, the test may be too short to fully deplete anaerobic energy reserves. We hypothesized that a 90-s all-out isokinetic test (ISO_90) would be valid to assess both aerobic and anaerobic capacities in young females. Eight girls (11.9 ± 0.5 y) performed an exhaustive incremental test, a WAnT and an ISO_90. Peak VO2 attained during the ISO_90 was significantly greater than VO2peak. Mean power, end power, fatigue index, total work done and AWC were not significantly different between the WAnT and after 30 s of the 90-s test (i.e., ISO_30). However, 95% limits of agreement showed large variations between the two tests when comparing all anaerobic parameters. It is concluded that an ISO-90 may be a useful test to assess aerobic capacity in young girls. However, since the anaerobic parameters derived from the ISO_30 did not agree with those derived from a traditional WAnT, the validity of using an ISO_90 to assess anaerobic performance and capacity within this population group remains unconfirmed.

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Amadeo F. Salvador, Rafael A. De Aguiar, Felipe D. Lisbôa, Kayo L. Pereira, Rogério S. de O. Cruz and Fabrizio Caputo

Although the amount of evidence demonstrating the beneficial effects of ischemic preconditioning (IPC) on exercise performance is increasing, conclusions about its efficacy cannot yet be drawn. Therefore, the purposes of this review were to determine the effect of IPC on exercise performance and identify the effects of different IPC procedures, exercise types, and subject characteristics on exercise performance. The analysis comprised 19 relevant studies from 2000 to 2015, 15 of which were included in the meta-analyses. Effect sizes (ES) were calculated as the standardized mean difference. Overall, IPC had a small beneficial effect on exercise performance (ES = 0.43; 90% confidence interval [CI], 0.28 to 0.51). The largest ES were found for aerobic (ES = 0.51; 90% CI, 0.35 to 0.67) and anaerobic (ES = 0.23; 90% CI, -0.12 to 0.58) exercise. In contrast, an unclear effect was observed in power and sprint performance (ES = 0.16; 90% CI, –0.20 to 0.52). In conclusion, IPC can effectively enhance aerobic and anaerobic exercise performance.

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Danny Too

The purpose of this investigation was to determine the effect of systematic changes in hip position/configuration on cycling peak anaerobic power (AP) and anaerobic capacity (AC). Fourteen male recreational cyclists (ages 21-32 yrs) were tested in four hip positions (25, 50, 75, and 100°), as defined by the angle formed by the seat tube and a vertical line. Rotating the seat to maintain a backrest perpendicular to the ground induced a systematic decrease in hip angle from the 25 to the 100° position. The Wingate anaerobic cycling test was used on a Monark cycle ergometer with a resistance of 85 gm/kg of the subject’s body mass. Repeated-measures MANOVAs and post hoc tests revealed that AP and AC in the 75° hip position were significantly greater than in the 25 or 100° position and that a second-order function best describes the trend in AP and AC with changes in hip position.

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Jonah D. Lee, Lauren E. Sterrett, Lisa M. Guth, Adam R. Konopka and Anthony D. Mahon

Carbohydrate (CHO) consumption before anaerobic exercise was studied in 13 adolescent boys (15.2 ± 0.9 yrs). A within subjects design was employed where subjects consumed a 22% CHO or volume-matched placebo (PL) beverage 30-min before anaerobic exercise on two separate days. Exercise consisted of a Wingate Anaerobic Test (WAnT), ten by 10-s-sprints, and a second WAnT. Fatigue index and peak power (PP) were similar while mean power (MP) was higher (p < .025) in CHO trial; however this difference was ascribed to initial WAnT performance. PP and MP for the 10-s sprints were similar between trials. Intravenous blood glucose and insulin concentrations were higher (p < .05) in the CHO trial while lactate and catecholamine concentrations were similar. Improved performance on a single WAnT was apparent with CHO consumption before exercise; however, this strategy did not attenuate fatigue over time in adolescent boys.

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Grant R. Tomkinson, Michael J. Hamlin and Timothy S. Olds

Secular changes in anaerobic fitness test performance in healthy 6- to 17-year-old Australasians were examined by meta-analysis of 232,564 power- and speed-test performances between 1960 and 2002. Overall, power-test performance improved at a rate of +0.05% [95% confidence interval (CI) = +0.01% to +0.09%] per annum, and speed at +0.04% (CI = +0.02% to +0.06%) per annum. Results indicate that anaerobic-fitness-test performances have remained relatively stable in Australasian children and adolescents in recent decades.

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Cory W. Baumann, Jeffrey C. Rupp, Christopher P. Ingalls and J. Andrew Doyle

Purpose:

The purpose of this study was to examine the relationship between anaerobic characteristics and 5-km-race performance in trained female cross-country runners (N = 13).

Methods:

The runners performed 50-m sprints and a 5-km time trial on an outdoor 400-m track and maximal anaerobic (MART) and aerobic running tests on a motorized treadmill. Anaerobic characteristics were determined by the mean velocity of the 50-m sprint (v 50m) and the peak velocity in the MART (v MART). The aerobic characteristics were obtained during the aerobic treadmill test and included maximal oxygen uptake (VO2max), running economy, and ventilatory threshold (VT).

Results:

Both the v MART (r = .69, P < .01) and VO2max (r = .80, P < .01) correlated with the mean velocity of the 5-km (v 5km). A multiple-linear-regression analysis revealed that the combination of VO2max, v MART, and VT explained 81% (R 2 = .81, P < .001) of the variation seen in the v 5km. The v MART accounted for 31% of the total shared variance, while the combination of VO2max and VT explained the remaining 50%.

Conclusions:

These results suggest that among trained female runners who are relatively matched, anaerobic energy production can effectively discriminate the v 5km and explain a significant amount of the variation seen in 5-km-race performance.