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Catrine Tudor-Locke, Meghan M. Brashear, Peter T. Katzmarzyk and William D. Johnson

Background:

Analysis of the 2005–2006 National Health and Nutrition Examination Survey (NHANES) accelerometer data provides the descriptive epidemiology of peak 30-minute cadence (defined as the average steps/min recorded for the 30 highest, but not necessarily consecutive, minutes in a day) and peak 1-minute cadence (defined as the steps/min recorded for the highest single minute in a day) by sex, age, and body mass index (BMI).

Methods:

Minute-by-minute step data were rank ordered each day to identify the peak 30-minute and 1-minute cadences for 3522 adults (20+ years of age) with complete sex, age, and BMI data and at least 1 valid day (ie, 10/24 hours of accelerometer wear) of accelerometer data. Peak values were averaged across days within participants by sex, age, and BMI-defined categories.

Results:

U.S. adults average a peak 30-minute cadence of 71.1 (men: 73.7, women: 69.6, P < .0001) steps/min and a peak 1-minute cadence of 100.7 (men: 100.9, women: 100.5, P = .54) steps/min. Both peak cadence indicators displayed significant and consistent declines with age and increasing levels of obesity.

Conclusions:

Peak cadence indicators capture the highest intensity execution of naturally occurring ambulatory activity. Future examination of their relationship with health parameters using cross-sectional, longitudinal, and intervention designs is warranted.

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Lee N. Burkett, Jack Chisum, Jack Pierce and Kent Pomeroy

Twenty spinal injured wheelchair bound individuals were tested to peak VO2 on a wheelchair ergometer. Sixteen subjects were paraplegics (5 females, 11 males) and four were quadriplegic (2 females, 2 males). The level of injury ranged from C4-5 to L2-3. The mean age of the subjects was 29.9 years, with a mean weight of 63.66 kg. Prior to the peak VO2 and during the rest immediately after peak VO2, each subject was tested for the ability to discriminate touch over the skin of the thigh, leg, and foot. A chi square statistical technique was used to test for differences between pre- and postexercise sensitivity. The chi square was significant at the .003 level of significance. Because the increase in sensitivity was short, it was theorized that under peak exercise stress the body may recruit pathways that have been dormant, but not injured, explaining the increase in sensitivity.

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Patrick J. Cohn

A qualitative study investigated the psychological characteristics of peak performance in golf. Nineteen professional and collegiate golfers (ages (19–38) participated in structured open-ended interviews. A content analysis of the interviews revealed that certain psychological qualities of peak performance exist among golfers. During peak performance the golfers were highly focused and immersed in the task at hand, performed effortlessly and automatically, felt physically relaxed and mentally calm, and felt in control of themselves and their performance. In addition, the golfers had no fear of negative consequences, maintained high self-confidence, and experienced fun and enjoyment. These results corroborate other studies examining peak performance with athletes in different sports. The results are discussed and suggestions are made for striving toward a unique and superior mental state.

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Jace A. Delaney, Heidi R. Thornton, John F. Pryor, Andrew M. Stewart, Ben J. Dascombe and Grant M. Duthie

Purpose:

To quantify the duration and position-specific peak running intensities of international rugby union for the prescription and monitoring of specific training methodologies.

Methods:

Global positioning systems (GPS) were used to assess the activity profile of 67 elite-level rugby union players from 2 nations across 33 international matches. A moving-average approach was used to identify the peak relative distance (m/min), average acceleration/deceleration (AveAcc; m/s2), and average metabolic power (Pmet) for a range of durations (1–10 min). Differences between positions and durations were described using a magnitude-based network.

Results:

Peak running intensity increased as the length of the moving average decreased. There were likely small to moderate increases in relative distance and AveAcc for outside backs, halfbacks, and loose forwards compared with the tight 5 group across all moving-average durations (effect size [ES] = 0.27–1.00). Pmet demands were at least likely greater for outside backs and halfbacks than for the tight 5 (ES = 0.86–0.99). Halfbacks demonstrated the greatest relative distance and Pmet outputs but were similar to outside backs and loose forwards in AveAcc demands.

Conclusions:

The current study has presented a framework to describe the peak running intensities achieved during international rugby competition by position, which are considerably higher than previously reported whole-period averages. These data provide further knowledge of the peak activity profiles of international rugby competition, and this information can be used to assist coaches and practitioners in adequately preparing athletes for the most demanding periods of play.

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Britton W. Brewer, Judy L. Van Raalte, Darwyn E. Linder and Nancy S. Van Raalte

Three experiments were conducted to determine which remembered qualities of the peak performance state are robust and to investigate whether recall biases may affect accounts of peak experiences. In the first experiment, introductory psychology students rated psychological characteristics of their best, average, and worst sport performances. Focused attention and confidence were the qualities most strongly identified with peak performance. The second experiment replicated and extended these findings in a sample of intercollegiate cross-country runners and tennis players. In the third experiment, subjects (a) completed a pursuit rotor task; (b) were randomly assigned to receive success, failure, or no feedback; and (c) rated their psychological state during performance. Results indicated that the bogus performance feedback significantly affected ratings of psychological states experienced during performance. Subjects given success feedback perceived themselves as being more confident and focused on the task than subjects given failure feedback. Implications of these findings for research and practice are discussed.

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Moran Sagiv, Michael Sagiv, Ehud Goldhammer and David Ben-Sira

Left ventricular function was evaluated in 14 adolescents (13.1 ± 1 years) at maximal oxygen uptake and at peak Wingate anaerobic test by means of echocardiography. Significant (p < .05) differences between aerobic and Wingate test bouts were found for: cardiac output (15.5 ± 1.2 and 12.2 ± 1.1 L/min, respectively); left ventricular end-systolic pressure—volume ratio (5.2 ± 0.8 and 6.0 ± 0.7, respectively); ejection fraction (72.2 ± 5.2 and 65.2 ± 5.1%, respectively); and mean arterial blood pressure (102.9 ± 10.8 and 111.1 ± 11.3 mmHg, respectively). Data suggest that left ventricular function at peak Wingate anaerobic test was markedly lower from that observed at peak aerobic exercise as a result of a higher afterload response.

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Tara K. Scanlan, David G. Russell, Noela C. Wilson and Larry A. Scanlan

We present an application of the Scanlan Collaborative Interview Method (SCIM) to the Project on Elite Athlete Commitment (PEAK). PEAK examines three samples of elite international athletes to further test and expand the Sport Commitment Model and assess its external validity. This first article in the series provides detailed descriptions of the study rationale, methods, procedures, interview schedule, and analysis strategy common to the three samples, along with participant characteristics and selection criteria. It also shares participants’ observations of the centrality of commitment to their athletic success, and their evaluation of the interview process.

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Erin M.R. Bigelow, Niell G. Elvin, Alex A. Elvin and Steven P. Arnoczky

To determine whether peak vertical and horizontal impact accelerations were different while running on a track or on a treadmill, 12 healthy subjects (average age 32.8 ± 9.8 y), were fitted with a novel, wireless accelerometer capable of recording triaxial acceleration over time. The accelerometer was attached to a custom-made acrylic plate and secured at the level of the L5 vertebra via a tight fitting triathlon belt. Each subject ran 4 miles on a synthetic, indoor track at a self-selected pace and accelerations were recorded on three perpendicular axes. Seven days later, the subjects ran 4 miles on a treadmill set at the individual runner’s average pace on the track and the peak vertical and horizontal impact magnitudes between the track and treadmill were compared. There was no difference (P = .52) in the average peak vertical impact accelerations between the track and treadmill over the 4 mile run. However, peak horizontal impact accelerations were greater (P = .0012) on the track when compared with the treadmill. This study demonstrated the feasibility for long-term impact accelerations monitoring using a novel wireless accelerometer.

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Philo U. Saunders, Amanda J. Cox, Will G. Hopkins and David B. Pyne

It is unclear whether physiological measures monitored in an incremental treadmill test during a training season provide useful diagnostic information about changes in distance running performance.

Purpose:

To quantify the relationship between changes in physiological measures and performance (peak running speed) over a training season.

Methods:

Well-trained distance runners (34 males; VO2max 64 ± 6 mL⋅kg-1⋅min-1, mean ± SD) completed four incremental treadmill tests over 17 wk. The tests provided values of peak running speed, VO2max, running economy, and lactate threshold (as speed and %VO2max). The physiological measures were included in simple and multiple linear regression models to quantify the relationship between changes in these measures and changes in peak speed.

Results:

The typical within-subject variation in peak speed from test to test was 2.5%, whereas those for physiological measures were VO2max (mL⋅min-1⋅kg-1) 3.0%, economy (m⋅kg⋅mL–1) 3.6%, lactate threshold (%VO2max) 8.7%, and body mass 1.8%. In simple models these typical changes predicted the following changes in performance: VO2max 1.4%, economy 0.8%, lactate threshold –0.3%, and body mass –0.2% (90% confidence limits ~±0.7%); the corresponding correlations with performance were 0.57, 0.33, –0.05, and –0.13 respectively (~±0.20). In a multiple linear regression model, the contribution of each physiological variable to performance changed little after adjustment for the other variables.

Conclusion:

Change in VO2max in an incremental test during a running season is a good predictor of change in peak running speed, change in running economy is a moderate predictor, and lactate threshold and body mass provide little additional information.

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Lasse Ishøi, Per Aagaard, Mathias F. Nielsen, Kasper B. Thornton, Kasper K. Krommes, Per Hölmich and Kristian Thorborg

, in part, be mediated by lower levels of peak eccentric hamstring muscle strength and muscle activation. 12 , 13 During sprinting, the stance phase has a duration of <200 milliseconds, 14 which shortens with increased sprinting velocity. 14 This implies that the ability of the hamstring muscles to