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Objective: This study examined the effects of speed deception on performance, physiological and perceptual responses, and pacing during sprint-distance triathlon running. Methods: Eight competitive triathletes completed three simulated sprint-distance triathlons (0.75 km swim, 20 km bike, 5 km run) in a randomised order, with swimming and cycling sections replicating baseline triathlon performance. During the first 1.66 km of the run participants maintained an imposed speed, completing the remaining 3.33 km as quickly as possible. Although participants were informed that initially prescribed running speed would reflect baseline performance, this was true during only one trial (Tri-Run 100% ). As such, other trials were either 3% faster (Tri-Run 103% ), or 3% slower (Tri-Run 97% ) than baseline during this initial period. Results: Performance during Tri-Run 103% (1346 ± 108 s) was likely faster than TriRun 97% (1371 ± 108 s), and possibly faster than Tri-Run 100% (1360 ± 125 s), with these differences likely to be competitively meaningful. The first 1.66 km of Tri-Run 103% induced greater physiological strain compared to other conditions, whilst perceptual responses were not significantly different between trials. Conclusions: It appears that even during 'all-out' triathlon running, athletes maintain some form of 'reserve' capacity which can be accessed by deception. This suggests that expectations and beliefs have a practically meaningful effect on pacing and performance during triathlon, although it is apparent that an individual's conscious intentions are secondary to the brains sensitivity to potentially harmful levels of physiological and perceptual strain.

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IntroductionThe benefits of unsupervised exercise programmes in obstructive lung disease are unclear. The aim of this systematic review was to synthesise evidence regarding the efficacy of unsupervised exercise versus non-exercise-based usual care in patients with obstructive lung disease.MethodsElectronic databases (MEDLINE, CINAHL, Embase, Allied and Complementary Medicine Database, Web of Science, Cochrane Central Register of Controlled Trials and Physiotherapy Evidence Database) and trial registers (ClinicalTrials.gov, Current Controlled Trials, UK Clinical Trials Gateway and WHO International Clinical Trials Registry Platform) were searched from inception to April 2020 for randomised trials comparing unsupervised exercise programmes with non-exercise-based usual care in adults with chronic obstructive pulmonary disease (COPD), non-cystic fibrosis bronchiectasis or asthma. Primary outcomes were exercise capacity, quality of life, mortality, exacerbations and respiratory cause hospitalisations.ResultsSixteen trials (13 COPD, 2 asthma, 1 chronic bronchitis: 1184 patients) met the inclusion criteria. Only data on COPD populations were available for meta-analysis. Unsupervised exercise resulted in a statistically but not clinically significant improvement in the 6-Minute Walk Test (n=5, MD=22.0 m, 95% CI 4.4 to 39.6 m, p=0.01). However, unsupervised exercise did lead to statistically significant and clinically meaningful improvements in St. George’s Respiratory Questionnaire (n=4, MD=−11.8 points, 95% CI −21.2 to −2.3 points, p=0.01) and Chronic Respiratory Disease Questionnaire domains (dyspnoea: n=4, MD=0.5 points, 95% CI 0.1 to 0.8 points, p<0.01; fatigue: n=4, MD=0.7 points, 95% CI 0.4 to 1.0 points, p<0.01; emotion: n=4, MD=0.5 points, 95% CI 0.2 to 0.7 points, p<0.01; mastery: unable to perform meta-analysis) compared with non-exercise-based usual care.DiscussionThis review demonstrates clinical benefits of unsupervised exercise interventions on health-related quality of life in patients with COPD. High-quality randomised trials are needed to examine the effectiveness of prescription methods.

A catalyst meeting on sexual selection studies was held in July 2013 at the facilities of the National Evolutionary Synthesis Center (NESCent) in Durham, NC. This article by a subcommittee of the participants foregrounds some of the topics discussed at the meeting. Topics mentioned here include the relevance of heritability estimates to assessing the presence of sexual selection, whether sexual selection is distinct from natural selection, and the utility of distinguishing sexual selection from fecundity selection. A possible definition of sexual selection is offered based on a distinction between sexual selection as a frequency-dependent process and fecundity selection as a density-dependent process. Another topic highlighted is a deep disagreement among participants in the reality of good-genes, sexy-sons, and run-away processes. Finally, the status of conflict in political-economic theory is contrasted with the status accorded to conflict in evolutionary behavioral theory, and the professional responsibility of sexual-selection workers to consider the ethical dimension of their research is underscored.