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Paddy C. Dempsey, Christine M. Friedenreich, Michael F. Leitzmann, Matthew P. Buman, Estelle Lambert, Juana Willumsen, and Fiona Bull

Background: In 2020, the World Health Organization (WHO) released global guidelines on physical activity (PA) and sedentary behavior, for the first time providing population-based recommendations for people living with selected chronic conditions. This article briefly presents the guidelines, related processes and evidence, and, importantly, considers how they may be used to support research, practice, and policy. Methods: A brief overview of the scope, agreed methods, selected chronic conditions (adults living with cancer, hypertension, type 2 diabetes, and human immunodeficiency virus), and appraisal of systematic review evidence on PA/sedentary behavior is provided. Methods were consistent with World Health Organization protocols for developing guidelines. Results: Moderate to high certainty evidence (varying by chronic condition and outcome examined) supported that PA can reduce the risk of disease progression or premature mortality and improve physical function and quality of life in adults living with chronic conditions. Direct evidence on sedentary behavior was lacking; however, evidence extrapolated from adult populations was considered applicable, safe, and likely beneficial (low certainty due to indirectness). Conclusions: Clinical and public health professionals and policy makers should promote the World Health Organization 2020 global guidelines and develop and implement services and programs to increase PA and limit sedentary behavior in adults living with chronic conditions.

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Shona L. Halson and David T. Martin

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Spencer E. Boyle, Melissa A. Fothergill, John Metcalfe, Sarah Docherty, and Crystal F. Haskell-Ramsay

Background: Physical activity provides a number of physical and psychological benefits. Multimodal proprioceptive exercise represents a useful balance-based exercise with the potential to reduce falls in older adults. Previous research has also indicated cognitive benefits following multimodal proprioceptive exercise in young and older adults. This study aimed to assess cognition and mood following 2 types of physical activity (multimodal proprioception vs yoga) compared with control (classroom-based) in healthy older adults. Method: Nineteen older adults (Mage = 65, sex = 9 males) participated in this randomized controlled crossover trial. Participants completed a 20-minute multimodal proprioceptive exercise class, 20-minute yoga session, and 20-minute classroom-based control. Numeric working memory and mood were assessed before and immediately following each of the interventions. Results: The multimodal proprioceptive intervention significantly reduced numeric working memory reaction time versus the yoga (P = .043) and control (P = .023) group. There were no differences found for accuracy or mood. Conclusions: These results indicate that multimodal proprioceptive exercise is worthy of further investigation as an alternative mode of exercise alongside the more traditional aerobic and strength-based exercise for healthy older adults.

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Neil D. Clarke and Darren L. Richardson

There is growing evidence that caffeine and coffee ingestion prior to exercise provide similar ergogenic benefits. However, there has been a long-standing paradigm that habitual caffeine intake may influence the ergogenicity of caffeine supplementation. The aim of the present study was to investigate the effect of habitual caffeine intake on 5-km cycling time-trial performance following the ingestion of caffeinated coffee. Following institutional ethical approval, in a double-blind, randomized, crossover, placebo-controlled design, 46 recreationally active participants (27 men and 19 women) completed a 5-km cycling time trial on a cycle ergometer 60 m in following the ingestion of 0.09 g/kg coffee providing 3 mg/kg of caffeine, or a placebo. Habitual caffeine consumption was assessed using a caffeine consumption questionnaire with low habitual caffeine consumption defined as <3 and ≥6 mg · kg−1 · day−1 defined as high. An analysis of covariance using habitual caffeine intake as a covariant was performed to establish if habitual caffeine consumption had an impact on the ergogenic effect of coffee ingestion. Sixteen participants were classified as high-caffeine users and 30 as low. Ingesting caffeinated coffee improved 5-km cycling time-trial performance by 8 ± 12 s; 95% confidence interval (CI) [5, 13]; p < .001; d = 0.30, with low, 9±14 s; 95% CI [3, 14]; p = .002; d = 0.18, and high, 8 ± 10 s; 95% CI [−1, 17]; p = .008; d = 0.06, users improving by a similar magnitude, 95% CI [−12, 12]; p = .946; d = 0.08. In conclusion, habitual caffeine consumption did not affect the ergogenicity of coffee ingestion prior to a 5-km cycling time trial.

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George P. Robinson, Sophie C. Killer, Zdravko Stoyanov, Harri Stephens, Luke Read, Lewis J. James, and Stephen J. Bailey

This study investigated whether supplementation with nitrate-rich beetroot juice (BR) can improve high-intensity intermittent running performance in trained males in normoxia and different doses of normobaric hypoxia. Eight endurance-trained males (V˙O2peak, 62 ± 6 ml·kg−1·min−1) completed repeated 90 s intervals at 110% of peak treadmill velocity, from an initial step incremental test, interspersed by 60 s of passive recovery until exhaustion (Tlim). Participants completed the first three experimental trials during days 3, 5, and 7 of BR or nitrate-depleted beetroot juice (PLA) supplementation and completed the remaining experimental visits on the alternative supplement following at least 7 days of washout. The fraction of inspired oxygen during visits 1–3 was either 0.209, 0.182, or 0.157, equivalent to an altitude of 0, 1,200, and 2,400 m, respectively, and this order was replicated on visits 4–6. Arterial oxygen saturation declined dose dependently as fraction of inspired oxygen was lowered (p < .05). Plasma nitrite concentration was higher pre- and postexercise after BR compared with PLA supplementation (p < .05). There was no difference in Tlim between PLA and BR at 0 m (445 [324, 508] and 410 [368, 548] s); 1,200 m (341 [270, 390] and 332 [314, 356] s); or 2,400 m (233 [177, 373] and 251 [221, 323] s) (median and [interquartile range]; p > .05). The findings from this study suggest that short-term BR supplementation does not improve high-intensity intermittent running performance in endurance-trained males in normoxia or at doses of normobaric hypoxia that correspond to altitudes at which athletes typically train while on altitude training camps.

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Farzin Halabchi, Reza Mazaheri, Khashayar Sabeti, Masoud Yunesian, Zahra Alizadeh, Zahra Ahmadinejad, Seyed Mojtaba Aghili, and Zahra Tavakol

Purpose: To compare the severity outcomes of COVID-19 disease between patients with and without regular sports participation. Methods: In a cross-sectional study, the authors investigated all patients who visited the emergency department of Imam Khomeini hospital with signs and symptoms of COVID-19 from February 20 to April 20, 2020. Then the authors assessed all patient outcomes (outpatient vs hospitalization or death). Finally, the authors compared the outcomes between athletes with regular sports participation and others, adjusting for confounding factors of age and sex. Results: Of all 4694 adult patients, 249 individuals (137 males and 112 females with mean [SD] age of 36.45 [9.77] y) had regular participation in different sport disciplines. Overall, 30 (12%) athletes were hospitalized or died (30 and 0, respectively) compared with 957 (21.5%) nonathletes (878 and 79, respectively). Athletes with regular sports participation were 1.49 times less likely to be hospitalized (P = .044). Conclusions: Regular sports participation may positively affect the clinical outcome, regardless of confounding factors of age and sex. The probability of hospitalization in athletes with regular sports participation was 33% lower than nonathletes. However, more longitudinal studies are needed to determine the causal effects.

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Michelle Ogrodnik, Jillian Halladay, Barbara Fenesi, Jennifer Heisz, and Katholiki Georgiades

Background: Participation in physical activity (PA) is a modifiable factor that contributes to academic success, yet the optimal dose (ie, frequency) and mechanisms underlying the effect require further exploration. Methods: Using data from 19,886 elementary and 11,238 secondary school students across Ontario, Canada, this study examined associations between PA participation frequency, academic achievement, and inattention and hyperactivity. Results: Among elementary students, there was a positive association between PA frequency and academic achievement. Participating in 1 to 2 days per week of PA related to higher academic achievement compared with no days, whereas 7 days per week had the largest associations. For secondary students, a minimum of 3 to 4 days per week was associated with higher academic achievement with no significant benefit of additional days. Indirect effects of inattention and hyperactivity were found for both groups, suggesting that the benefits of PA on academic achievement may be partly explained by reductions in inattention and hyperactivity, especially for secondary school students. Conclusion: Students may experience academic benefits from PA even if they are not meeting the guidelines of exercising daily. These benefits may occur, in part, through reductions in inattention and hyperactivity. Further work is needed to determine the temporality and mechanism of these associations.

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Jessica Gorzelitz, Chloe Farber, Ronald Gangnon, and Lisa Cadmus-Bertram

Background: The evidence base regarding validity of wearable fitness trackers for assessment and/or modification of physical activity behavior is evolving. Accurate assessment of moderate- to vigorous-intensity physical activity (MVPA) is important for measuring adherence to physical activity guidelines in the United States and abroad. Therefore, this systematic review synthesizes the state of the validation literature regarding wearable trackers and MVPA. Methods: A systematic search of the PubMed, Scopus, SPORTDiscus, and Cochrane Library databases was conducted through October 2019 (PROSPERO registration number: CRD42018103808). Studies were eligible if they reported on the validity of MVPA and used devices from Fitbit, Apple, or Garmin released in 2012 or later or available on the market at the time of review. A meta-analysis was conducted on the correlation measures comparing wearables with the ActiGraph. Results: Twenty-two studies met the inclusion criteria; all used a Fitbit device; one included a Garmin model and no Apple-device studies were found. Moderate to high correlations (.7–.9) were found between MVPA from the wearable tracker versus criterion measure (ActiGraph n = 14). Considerable heterogeneity was seen with respect to the specific definition of MVPA for the criterion device, the statistical techniques used to assess validity, and the correlations between wearable trackers and ActiGraph across studies. Conclusions: There is a need for standardization of validation methods and reporting outcomes in individual studies to allow for comparability across the evidence base. Despite the different methods utilized within studies, nearly all concluded that wearable trackers are valid for measuring MVPA.