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The Effects of Wearing Lower Body Compression Garments During a Cycling Performance Test

Matthew W. Driller and Shona L. Halson

Purpose:

Compression garments have been commonly used in a medical setting as a method to promote blood flow. Increases in blood flow during exercise may aid in the delivery of oxygen to the exercising muscles and, subsequently, enhance performance. The aim of the current study was to investigate the effect of wearing lower body compression garments during a cycling test.

Methods:

Twelve highly trained cyclists (mean ± SD age 30 ± 6 y, mass 75.6 ± 5.8 kg, VO2peak 66.6 ± 3.4 mL · kg−1 · min−1) performed two 30-min cycling bouts on a cycle ergometer in a randomized, crossover design. During exercise, either full-length lower body compression garments (COMP) or above-knee cycling shorts (CON) were worn. Cycling bouts involved 15 min at a fixed workload (70% of VO2max power) followed by a 15-min time trial. Heart rate (HR) and blood lactate (BL) were measured during the fixed-intensity component of the cycling bout to determine the physiological effect of the garments. Calf girth (CG), thigh girth (TG) and perceived soreness (PS) were measured preexercise and postexercise.

Results:

COMP produced a trivial effect on mean power output (ES = .14) compared with CON (mean ± 95% CI 1.3 ±1.0). COMP was also associated with a lower HR during the fixed-workload section of the test (−2.6% ± 2.3%, ES = −.38). There were no differences between groups for BL, CG, TG, and PS.

Conclusion:

Wearing compression garments during cycling may result in trivial performance improvements of ~1% and may enhance oxygen delivery to the exercising muscles.

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University Student’s Perceptions of Self-Tracking Devices, Data Privacy, and Sharing Digital Data for Research Purposes

Marianne I. Clark and Matthew W. Driller

Purpose: Wearable physical activity monitors present new ethical considerations for researchers and research ethics boards. Best practice guidelines are needed for research involving wearable monitors and should consider how these devices may impact participants outside of the research context. This study examines the perceptions of university students who wore activity monitors for research purposes in order to inform such guidelines. Methods: Focus groups were held with university students who wore digital self-tracking devices for a study examining sleep and physical activity. Questions focused on motivations to wear a physical activity monitor for research, understandings of how personal digital data generated by self-tracking devices are used and accessed, and perceptions of privacy. Results: 83% of students trusted the research process and were motivated to contribute to scientific knowledge by wearing a digital tracking device. Most (83%) understood how their data were used and accessed for research purposes, but 79% were less clear on how data might be accessed and used by third parties. 79% of participants also agreed that different data carries different social and personal implications and thus should not be treated the same by researchers. Conclusions: Protocols for research involving wearable monitors should include briefing/debriefing sessions to clarify data privacy, storage, and use issues. Researchers should also consider how wearing these devices might prompt unexpected emotional and other responses and the social implications of use for participants. The concept of privacy requires further exploration in the context of digital data collection using commercial devices.

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Pneumatic Compression Fails to Improve Performance Recovery in Trained Cyclists

Ryan G. Overmayer and Matthew W. Driller

Purpose: To examine the efficacy of intermittent sequential pneumatic compression (ISPC) on exercise recovery and subsequent performance, when implemented between a 20-min cycling bout (simulated scratch race) and a 4-min cycling test (simulated individual pursuit), as experienced during an Omnium track cycling competition. Methods: Twenty-one (13 male and 8 female, mean [SD]: age = 36 [14] y) trained cyclists completed a familiarization trial followed by 2 experimental trials in a counterbalanced, cross-over design. Participants performed a fixed-intensity 20-min cycling bout on a Wattbike cycle ergometer, followed by a 30-min recovery period where ISPC recovery boots or passive recovery was implemented. At the conclusion of the recovery period, participants performed a 4-min maximal cycling bout (4-min time trial [TT]). Average power (watts) for the 4-min TT, blood lactate concentration, and perceived total quality recovery (TQR) during the recovery period were used to examine the influence of ISPC. Results: There were no significant differences between trials for the 4-min TT (P = .08), with the effect deemed to be trivial (d = −0.08). There was an unclear effect (d [±90% confidence interval] = 0.26 [±0.78], P = .57) for ISPC vs passive recovery in the clearance of blood lactate during the recovery period. There was a small but not significant difference for perceived TQR in favor of ISPC (d [±90% confidence interval] = 0.27 [±0.27], P = .07). Conclusion: There was little additional benefit associated with the use of ISPC to enhance recovery and subsequent performance when used during the recovery period between 2 events in a simulated Omnium track cycling competition.

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A Strategy to Inform Athlete Sleep Support From Questionnaire Data and Its Application in an Elite Athlete Cohort

Haresh T. Suppiah, Paul B. Gastin, and Matthew W. Driller

Purpose: Information from the Pittsburgh Sleep Quality Index (PSQI) and Athlete Sleep Behavior Questionnaire (ASBQ) provide the ability to identify the sleep disturbances experienced by athletes and their associated athlete-specific challenges that cause these disturbances. However, determining the appropriate support strategy to optimize the sleep habits and characteristics of large groups of athletes can be time-consuming and resource-intensive. The purpose of this study was to characterize the sleep profiles of elite athletes to optimize sleep-support strategies and present a novel R package, AthSlpBehaviouR, to aid practitioners with athlete sleep monitoring and support efforts. Methods: PSQI and ASBQ data were collected from a cohort of 412 elite athletes across 27 sports through an electronic survey. A k-means cluster analysis was employed to characterize the unique sleep-characteristic typologies based on PSQI and ASBQ component scores. Results: Three unique clusters were identified and qualitatively labeled based on the z scores of the PSQI components and ASBQ components: cluster 1, “high-priority; poor overall sleep characteristics + behavioral-focused support”; cluster 2, “medium-priority, sleep disturbances + routine/environment-focused support”; and cluster 3, “low-priority; acceptable sleep characteristics + general support.” Conclusions: The findings of this study highlight the practical utility of an unsupervised learning approach to perform clustering on questionnaire data to inform athlete sleep-support recommendations. Practitioners can consider using the AthSlpBehaviouR package to adopt a similar approach in athlete sleep screening and support provision.

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The Reliability of a 30-s Sprint Test on the Wattbike Cycle Ergometer

Matthew W. Driller, Christos K. Argus, and Cecilia M. Shing

Purpose:

To determine the reliability of a 30-s sprint cycle test on the Wattbike cycle ergometer.

Methods:

Over 3 consecutive weeks, 11 highly trained cyclists (mean ± SD; age 31 ± 6 y, mass 74.6 ± 10.6 kg, height 180.5 ± 8.1cm) completed four 30-s maximal sprints on a Wattbike ergometer after a standardized warmup. The sprint test implemented a “rolling start” that consisted of a 60-s preload (at an intensity of 4.5 W/kg) before the 30-s maximal sprint. Variables determined across the duration of the sprint were peak power (Wpeak), mean power (Wmean), W/kg, mean cadence (rpm), maximum heart rate (n = 10), and postexercise blood lactate.

Results:

The average intraclass correlation coefficients between trials (2v1, 3v2, 4v3, 4v1) were Wpeak .97 (90%CI .94–.99), Wmean .99 (90%CI .97–1.00), W/kg .96 (90%CI .91–.98), mean cadence .96 (90%CI .92–.99), maximum heart rate .99 (90%CI .97–.99), and postexercise blood lactate .94 (90%CI .87–.98). The average typical error of measurement (expressed as a CV% and absolute value between trials—2v1, 3v2, 4v3, 4v1) was Wpeak 4.9%, 52.7 W; Wmean 2.4%, 19.2 W; W/kg 2.3%, 0.18 W/kg; mean cadence 1.4%, 1.6 rpm; maximum heart rate 0.9%, 1.6 beats/min; and postexercise blood lactate 4.6%, 0.48 mmol/L.

Conclusion:

A 30-s sprint test on the Wattbike cycle ergometer is highly reproducible in trained cyclists.

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The Effects of Chronic Sodium Bicarbonate Ingestion and Interval Training in Highly Trained Rowers

Matthew W. Driller, John R. Gregory, Andrew D. Williams, and James W. Fell

Recent research has reported performance improvements after chronic NaHCO3 ingestion in conjunction with high-intensity interval training (HIT) in moderately trained athletes. The purpose of the current study was to determine the effects of altering plasma H+ concentration during HIT through NaHCO3 ingestion over 4 wk (2 HIT sessions/wk) in 12 Australian representative rowers (M ± SD; age 22 ± 3 yr, mass 76.4 ± 4.2 kg, VO2peak 65.50 ± 2.74 ml · kg−1 · min−1). Baseline testing included a 2,000-m time trial and an incremental exercise test. After baseline testing, rowers were allocated to either a chronic NaHCO3 (ALK) or placebo (PLA) group. Starting 90 min before each HIT session, subjects ingested a 0.3-g/kg body mass dose of NaHCO3 or a placebo substance. Fingertip blood samples were taken throughout the study to analyze bicarbonate and pH levels. The ALK group did not produce any additional improvements in 2,000-m rowing performance time compared with PLA (p > .05). Magnitude-based inferential analysis indicated an unclear or trivial effect on 2,000-m power, 2,000-m time, peak power output, and power at 4 mmol/L lactate threshold in the ALK group compared with the PLA group. Although there was no difference between groups, during the study there was a significant mean (± SD) 2,000-m power improvement in both the ALK and PLA groups of 17.8 ± 14.5 and 15.2 ± 18.3 W, respectively. In conclusion, despite overall improvements in rowing performance after 4 wk of HIT, the addition of chronic NaHCO3 supplementation during the training period did not significantly enhance performance further.

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The Effect of Beta-Alanine Supplementation on Isokinetic Force and Cycling Performance in Highly Trained Cyclists

Samuel T. Howe, Phillip M. Bellinger, Matthew W. Driller, Cecilia M. Shing, and James W. Fell

Beta-alanine may benefit short-duration, high-intensity exercise performance. The aim of this randomized double-blind placebo-controlled study was to examine the effects of beta-alanine supplementation on aspects of muscular performance in highly trained cyclists. Sixteen highly trained cyclists (mean ± SD; age = 24 ± 7 yr; mass = 70 ± 7kg; VO2max = 67 ± 4ml·kg−1·min–1) supplemented with either beta-alanine (n = 8, 65 mg·kg−1BM) or a placebo (n = 8; dextrose monohydrate) over 4 weeks. Pre- and postsupplementation cyclists performed a 4-minute maximal cycling test to measure average power and 30 reciprocal maximal isokinetic knee contractions at a fixed angular velocity of 180°·sec−1 to measure average power/repetition, total work done (TWD), and fatigue index (%). Blood pH, lactate (La) and bicarbonate (HCO3 -) concentrations were measured preand postisokinetic testing at baseline and following the supplementation period. Beta-alanine supplementation was 44% likely to increase average power output during the 4-minute cycling time trial when compared with the placebo, although this was not statistically significant (p = .25). Isokinetic average power/repetition was significantly increased post beta-alanine supplementation compared with placebo (beta-alanine: 6.8 ± 9.9W, placebo: –4.3 ± 9.5 W, p = .04, 85% likely benefit), while fatigue index was significantly reduced (p = .03, 95% likely benefit). TWD was 89% likely to be improved following beta-alanine supplementation; however, this was not statistically significant (p = .09). There were no significant differences in blood pH, lactate, and HCO3 between groups (p > .05). Four weeks of beta-alanine supplementation resulted in worthwhile changes in time-trial performance and short-duration muscular force production in highly trained cyclists.

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Effect of Compression Socks Worn Between Repeated Maximal Running Bouts

Ned Brophy-Williams, Matthew W. Driller, Cecilia M. Kitic, James W. Fell, and Shona L. Halson

Purpose:

To determine the effect of wearing compression socks between repeated running bouts on perceptual, physiological, and performance-based parameters.

Methods:

Twelve well-trained male runners (mean ± SD 5-km time 19:24 ± 1:19 [min:s]) recorded their perceptions of the efficacy of compression socks for recovery before completion of 2 experimental sessions. Each session consisted of two 5-km running time trials (TT1 and TT2) on a treadmill, with a 1-h recovery period between. In a randomized crossover design, 1 session required participants to wear compression socks during the recovery period, and no compression socks were worn between TTs in the other session (control).

Results:

Running performance between TT1 and TT2 for runners wearing compression socks was similar between TTs (mean Δ 5.3 ± 20.7 s, d = 0.07, P = .20), whereas for control runners, performance significantly decreased in the second TT (mean Δ 15.9 ± 13.3 s, d = 0.19, P < .01). When grouped by perception of efficacy for compression socks, participants with strong beliefs (n = 7) experienced improved subsequent running performance with compression socks (mean Δ –3.6 ± 19.2 s, d = 0.05, P = .32) compared with those with neutral or negative perceptions (n = 5; mean Δ 17.9 ± 17.0 s, d = 0.19, P = .04). Cross-sectional area of the calf and muscle soreness were significantly reduced during the recovery period with the use of compression socks (P < .01), whereas ratings of fatigue showed no difference between conditions.

Conclusions:

Wearing compression socks between repeated running bouts can aid recovery and subsequent performance. Furthermore, subsequent exercise performance may be even further enhanced when athletes believe in the efficacy of compression socks to assist in recovery between exercise bouts.

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The Effects of High-Intensity Interval Training in Well-Trained Rowers

Matthew W. Driller, James W. Fell, John R. Gregory, Cecilia M. Shing, and Andrew D. Williams

Purpose:

Several recent studies have reported substantial performance and physiological gains in well-trained endurance runners, swimmers, and cyclists following a period of high-intensity interval training (HIT). The aim of the current study was to compare traditional rowing training (CT) to HIT in well-trained rowers.

Methods:

Subjects included 5 male and 5 female rowers (mean ± SD; age = 19 ± 2 y; height = 176 ± 8 cm; mass = 73.7 ± 9.8 kg; Vo2peak = 4.37 ± 1.08 L·min−1). Baseline testing included a 2000-m time trial and a maximal exercise test to determine Vo2peak, 4-min all-out power, and 4 mmol·L−1 blood lactate threshold. Following baseline testing, rowers were randomly allocated to HIT or CT, which they performed seven times over a 4-wk period. The HIT involved 8 × 2.5-min intervals at 90% of the velocity maintained at Vo2peak, with individual recoveries returning to 70% of the subjects’ maximal heart rate between intervals. The CT intensity consisted of workloads corresponding to 2 and 3 mmol·L−1 blood lactate concentrations. On completion of HIT or CT, rowers repeated the testing performed at baseline and were then allocated to the alternative training program and completed a crossover trial.

Results:

HIT produced greater improvements in 2000-m time (1.9 ± 0.9%; mean ± SD), 2000-m power (5.8 ± 3.0%), and relative Vo2peak (7.0 ± 6.4%) than CT.

Conclusion:

Four weeks of HIT improves 2000-m time-trial performance and relative Vo2peak in competitive rowers, more than a traditional approach.

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The Effects of 4 Different Recovery Strategies on Repeat Sprint-Cycling Performance

Christos K. Argus, Matthew W. Driller, Tammie R. Ebert, David T. Martin, and Shona L. Halson

Purpose:

To evaluate the effectiveness of different recovery strategies on repeat cycling performance where a short duration between exercise bouts is required.

Methods:

Eleven highly trained cyclists (mean ± SD; age = 31 ± 6 y, mass = 74.6 ± 10.6 kg, height = 180.5 ± 8.1 cm) completed 4 trials each consisting of three 30-s maximal sprints (S1, S2, S3) on a cycle ergometer, separated by 20-min recovery periods. In a counterbalanced, crossover design, each trial involved subjects performing 1 of 4 recovery strategies: compression garments (COMP), electronic muscle stimulation (EMS), humidification therapy (HUM), and a passive control (CON). The sprint tests implemented a 60-s preload (at an intensity of 4.5 W/kg) before a 30-s maximal sprint. Mean power outputs (W) for the 3 sprints, in combination with perceived recovery and blood lactate concentration, were used to examine the effect of each recovery strategy.

Results:

In CON, S2 and S3 were (mean ± SD) –2.1% ± 3.9% and –3.1% ± 4.2% lower than S1, respectively. Compared with CON, COMP resulted in a higher mean power output from S1 to S2 (mean ± 90%CL: 0.8% ± 1.2%; possibly beneficial) and from S1 to S3 (1.2% ± 1.9%; possibly beneficial), while HUM showed a higher mean power output from S1 to S3 (2.2% ± 2.5%; likely beneficial) relative to CON.

Conclusion:

The authors suggest that both COMP and HUM may be effective strategies to enhance recovery between repeated sprint-cycling bouts separated by ~30 min.