Early-Morning and Late-Night Maximal Runs: Metabolic and Perceived Exertion Outcomes

People may exercise at the ends of their day to fit activity into their schedule; the purpose of this investigation was to determine if metabolic or perceived exertion outcomes differed between maximal runs early in the morning and late at night. After consuming a standardized, glucose drink, thirteen recreationally active individuals completed an early-morning and a late-night run on the treadmill while researchers measured metabolic (aerobic capacity and substrate usage) and perceived exertion outcomes. Point of application #1: Aerobic capacity (maximal consumption of oxygen) and the usage of fat as a fuel to support energy production during exercise were similar between runs. Point of application #2: Maximal perceived exertion (Borg’s 6-20) was similar during early-morning and late-night runs. Point of application #3: While research indicates that people may prefer activity in the morning or evening, and this might impact metabolic responses to the exercise bout, most of our participants (n=8) identified with no preference for exercising in the early-morning or late-night. Key Words: glucose; CHO shake; VO2max; fat oxidation; effor

Establishing a Methodology for Conducting a Rapid Review on Wearable Technology Reliability and Validity in Applied Settings

Wearable technology is becoming increasingly popular with new devices entering the market frequently, but with disproportionality less research being conducted on the reliability and validity in field settings, outside of the laboratory. This paper details the methodology of gathering research based on the principals of a rapid review, using these points of application: inclusion criteria of studies (databases), search terms (data to be extracted), and how research will be conducted (narrowing articles and assessing bias). Point of application #1: Inclusion criteria are described well as potential databases used, allowing a means of not only systematically gathering information, but also the ability to check the status of the literature regarding wearable technology. Point of application #2: Specific search terms are outlined, and the data fields to be extracted are described. Point of application #3: Mechanism of the rapid review search explained, how articles are to be included and excluded, and how bias will be assessed

Validity of Garmin Devices while Ascending and Descending Flights of Stairs

The use of wearable technology to track physical activity is popular among fitness enthusiasts and the general public. There are many brands that offer a variety of devices. One popular brand is Garmin. The validity of Garmin’s wrist-worn devices in measuring step counts in various settings, such as walking up and down a staircase, is unclear. PURPOSE: The purpose of the present study was to determine if two devices, the Garmin fēnix 5 and Garmin vívosmart HR record valid measures of step count when ascending and descending flights of stairs at three different speeds. METHODS: Twenty participants (n=20) were tested individually. The Garmin fēnix 5 and Garmin vívosmart HR were worn on separate wrists (placement was randomly selected). Participants climbed up then down one, two, and three flights of stairs (19, 39, and 59 steps, respectively [manual count]) at speeds of 50, 75, and 100, beats per minute (bpm) for a total of 18 trials. The step counts provided by both devices were recorded before and after each up and down trial. Each trial was separated by 2-3 minutes of rest. Mean absolute percent error (MAPE, ≤10%) and Lin’s Concordance (CCC, ≥0.7) were used to validate the device step counts with the actual number of steps. Dependent T-tests determined differences (p≤0.05). RESULTS: The only condition that was considered valid was descending stairs at 100 bpm using the Garmin vívosmart (see table). CONCLUSION: Individuals who ascend and descend numerous stairs during their day may wish to consider the implications of these findings

A Systematic Review of the Effects of Meditative and Mindful Walking on Mental and Cardiovascular Health

International Journal of Exercise Science 15(2): 1692-1734, 2022. Meditative and mindful exercise are types of physical exercise during which people pay attention, on purpose, to each new present moment without judging their experience. The goal is to apply an accepting awareness of the environment, bodily sensations, thoughts, and emotions without labeling them (e.g., good or bad). The literature centers on qigong, tai chi, and yoga, which are types of mindful exercise that improve mental and cardiovascular health. It is unclear if meditative and mindful walking also improve these health domains. To the authors’ knowledge, this question has not been addressed by a published systematic review. The purpose of this systematic review without a meta-analysis was to synthesize the literature on meditative and mindful walking to determine their effects on mental and cardiovascular health. The protocol follows the PRISMA guidelines, is registered in PROSPERO (CRD42021241180), and is published elsewhere in a peer-reviewed journal. The systematic review contains 14 studies that had various populations, interventions, and outcomes. In 13 studies, the interventions statistically significantly improved scores on at least one outcome of mental or cardiovascular health (e.g., affect, anxiety, depression, distress, state mindfulness, stress, blood pressure, and six-minute walk distance). The improved outcomes should be interpreted cautiously because their clinical meaningfulness is unclear, and the studies had severe methodological limitations. Determining if meditative and mindful walking meaningfully improve mental and cardiovascular health will require randomized controlled trials that use rigorous designs, transparent protocols, and clinically meaningful outcomes that indicate physical function, mental wellbeing, morbidity, and mortality

Efficient Method of Delivery for Powdered Supplement or Placebo for an Outdoor Exercise Investigation

Researchers often encounter issues while attempting to deliver complete doses of a desired supplement/placebo when conducting research in outdoor environments. The problem faced by our research team was how to efficiently deliver 6.4 grams of Beta Alanine (BA) powder to subjects while conducting a hiking study on a windy trail in Southern Utah. To minimize the potential impact of the weather, and to maximize the efficiency of delivery, we determined a premixed bolus of BA contained in individual commercially available 8oz water bottles was the most efficient delivery method. The purpose of this article is to detail the development and implementation of this method. Point of Application 1: Testing solubility, and efficacy of dissolved BA Point of Application 2: Producing a large volume of pre-mixed supplement-bottles and placebo-bottles Point of Application 3: On site administration of supplement and placeb

Postnatal β2 adrenergic treatment improves insulin sensitivity in lambs with IUGR but not persistent defects in pancreatic islets or skeletal muscle

Placental insufficiency causes intrauterine growth restriction (IUGR) and disturbances in glucose homeostasis with associated β adrenergic receptor (ADRβ) desensitization. Our objectives were to measure insulin-sensitive glucose metabolism in neonatal lambs with IUGR and to determine whether daily treatment with ADRβ2 agonist and ADRβ1/β3 antagonists for 1 month normalizes their glucose metabolism. Growth, glucose-stimulated insulin secretion (GSIS) and glucose utilization rates (GURs) were measured in control lambs, IUGR lambs and IUGR lambs treated with adrenergic receptor modifiers: clenbuterol atenolol and SR59230A (IUGR-AR). In IUGR lambs, islet insulin content and GSIS were less than in controls; however, insulin sensitivity and whole-bodyGUR were not different from controls.Of importance, ADRβ2 stimulation with β1/β3 inhibition increases both insulin sensitivity and whole-body glucose utilization in IUGR lambs. In IUGR and IUGR-AR lambs, hindlimb GURs were greater but fractional glucose oxidation rates and ex vivo skeletal muscle glucose oxidation rates were lower than controls. Glucose transporter 4 (GLUT4) was lower in IUGR and IUGR-AR skeletal muscle than in controls but GLUT1 was greater in IUGR-AR. ADRβ2, insulin receptor, glycogen content and citrate synthase activity were similar among groups. In IUGR and IUGR-AR lambs heart rates were greater, which was independent of cardiac ADRβ1 activation. We conclude that targeted ADRβ2 stimulation improved whole-body insulin sensitivity but minimally affected defects in GSIS and skeletal muscle glucose oxidation. We show that risk factors for developing diabetes are independent of postnatal catch-up growth in IUGR lambs as early as 1 month of age and are inherent to the islets and myocytes

The Validity and Reliability of the Garmin Instinct in Measuring Heart Rate, Energy Expenditure, and Steps During Skipping

As the use of wearable technology to monitor physical activity increases, assessment of the validity and reliability of these devices are needed. A popular device brand is Garmin. Although not a common physical activity, skipping can be included in dynamic warm-ups. PURPOSE: Therefore, the purpose of this study was to determine the validity and reliability of the Garmin Instinct in measuring caloric energy expenditure (EE), average heart rate (HR), and steps while skipping. METHODS: Ten participants (5 female, age: 27±9 years) skipped at a self-selected pace for five minutes. During that time, HR, EE, and steps were measured by the Polar H10, Cosmed K5, and manual counting, respectively. Two Garmin Instincts simultaneously tracked all three variables. A step was defined as any time the foot leaves and hits the ground (stride x 4). Data was input into Google Sheets and summary statistics, t-test with Bonferonni corrections, and mean absolute percentage error (MAPE) were calculated. Additional validity and reliability tests were run in jamovi, including Lin’s concordance correlation coefficient (CCC), TOST tests, Bland-Altman bias, coefficient of variation (CV), and intraclass correlation coefficient (ICC). The pre-established validity criteria are as follows: CCC \u3e 0.7 and MAPE \u3c 10%. The pre-established reliability criteria are as follows: CV \u3c 10% and ICC \u3e 0.7. RESULTS: The Garmin Instinct had a MAPE of 19.2%, 28.5%, and 53.2% for HR, EE, and steps, respectively. It had a CCC of .06, .21, and .01 for HR, EE, and steps, respectively. The 2-tailed paired t-tests with corrections for multiple comparisons was significant for HR and steps. The TOST tests were violated for all 3 measurements (HR, EE, and steps). Bland-Altman analysis produced a bias estimate of 34.0, 0.6, and 1100 for HR, EE, and steps, respectively. The Garmin produced a CV of 11.2%, 14.8%, and 6.6% for HR, EE, and steps, respectively. It produced an ICC of .51, .64, and .81 for HR, EE, and steps, respectively. CONCLUSION: The Garmin Instinct did not meet the pre-established validity criteria for any measure (HR, EE, or steps). However, it did meet the pre-established reliability criteria for steps but not for HR or EE. Therefore, the Garmin Instinct cannot be expected to produce accurate estimates of HR, EE, or steps during skipping

Endothelial function and arterial stiffness in young adults with histories of chronic resistance activity

Endothelial dysfunction and arterial stiffness indicate vessel damage and are detectable before overt cardiovascular disease. Chronic cardiorespiratory endurance activity improves arterial endothelial function and stiffness. The influence of chronic resistance activity on these variables is less definitive and thus deserves attention. The primary aim of this investigation was to determine if endothelial dysfunction and arterial stiffness were present in apparently healthy young adults who chronically engage in resistance activity with minimal cardiorespiratory endurance activity. Investigators measured endothelial function as LnRHI and arterial stiffness as AI@75 using the EndoPAT-2000. Investigators measured upper-body muscular strength using a standardized one-repetition maximum (1-RM) bench press. The LnRHI and AI@75 between males and females were compared via an independent-samples t-test and Mann-Whitney U test, respectively. Correlations between 1-RM, bench press to body weight ratio, LnRHI, and AI@75 were evaluated via Pearson’s correlation. Males’ LnRHI was abnormal according to manufacturer standards and lower than females’ (p = .005), but AI@75 was normal and similar for both sexes (p = .22). The 1-RM and bench press to body weight ratio correlated negatively with LnRHI (p = .03 and p = .01, respectively). The bench press to body weight ratio correlated negatively with AI@75 (p = .03), and percentage body fat correlated positively with the AI@75 (p = .003). Young adult males with considerable upper-body muscular strength due to chronic resistance activity, who complete minimal cardiorespiratory endurance activity, appear to have detectable signs of early endothelial dysfunction

A Protocol and Novel Tool for Systematically Reviewing the Effects of Mindful Walking on Mental and Cardiovascular Health

To our knowledge, no published systematic review has described the effects of mindful walking on mental and cardiovascular health. We have aimed to fill this gap by first establishing our systematic review protocol. Our protocol was adapted from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and is registered in PROSPERO (Registration Number: CRD42021241180). The protocol is described step-by-step in this paper, which we wrote to achieve three objectives: to adhere to the best practices stated in the PRISMA guidelines, to ensure procedural transparency, and to enable readers to co-opt our protocol for future systematic reviews on mindful walking and related topics. To achieve our third objective, we provide and explain a novel tool we created to track the sources we will find and screen for our review. Ultimately, the protocol and novel tool will lead to the first published systematic review about mindful walking and will also facilitate future systematic reviews

Assessing the Validity of Several Heart Rate Monitors in Wearable Technology While Mountain Biking

International Journal of Exercise Science 16(7): 1440-1450, 2023. Purpose: This study sought to assess the validity of several heart rate (HR) monitors in wearable technology during mountain biking (MTB), compared to the Polar H7® HR monitor, used as the criterion device. Methods: A total of 20 participants completed two MTB trials while wearing six HR monitors (5 test devices, 1 criterion). HR was recorded on a second-by-second basis for all devices analyzed. After data processing, validity measures were calculated, including 1. error analysis: mean absolute percentage errors (MAPE), mean absolute error (MAE), and mean error (ME), and 2. Correlation analysis: Lin’s concordance correlation coefficient (CCC) and Pearson’s correlation coefficient (r). Thresholds for validity were set at MAPE \u3c 10% and CCC \u3e 0.7. Results: The only device that was found to be valid during mountain biking was the Suunto Spartan Sport watch with accompanying HR monitor, with a MAPE of 0.66% and a CCC of 0.99 for the overall, combined data. Conclusion: If a person would like to track their HR during mountain biking, for pacing, training, or other reasons, the devices best able to produce valid results are chest-based, wireless electrocardiogram (ECG) monitors, secured by elastic straps to minimize the movement of the device, such as the Suunto chest-based HR monitor