Is Body Composition or Body Mass Index Associated with the Step Count Accuracy of a Wearable Technology Device?

Topics in Exercise Science and Kinesiology Volume 3: Issue 1, Article 5, 2022. A simple way to gauge daily physical activity levels is to use a wearable technology device to count the number of steps taken during the day. However, it is unknown whether these devices return accurate step counts for persons with different body fat percentages or body mass index scores. The purpose was to determine if there is a correlation between either body fat percentages and/or body mass index values and the percent error calculated between a manual step count and values recorded by a wearable technology device. Forty volunteers participated. The Samsung Gear 2, FitBit Surge, Polar A360, Garmin Vivosmart HR+, and the Leaf Health Tracker were evaluated when walking and jogging in free motion and treadmill conditions. All devices were worn simultaneously in randomized configurations. The mean of two manual steps counters was used as the criterion measure. Walking and jogging free motion and treadmill protocols of 5-minute intervals were completed. Correlation was determined by Spearman’s rank correlation coefficient. Significance was set at \u3c0.05. There were no significant correlations for body mass index vs percent error. For body fat, significant positive correlations were observed for the Samsung Gear 2 free motion walk: (r=0.321, p=0.043), Garmin Vivosmart HR+ free motion walk: (r=0.488, p=\u3c0.001), and the Leaf Health Tracker treadmill walk: (r=0.368, p=0.020) and treadmill jog: (r=0.350, p=0.027). Body fat may have a limited association with a device’s step count percent error. Lower body mechanics along with device placement may be more of a factor in step counting accuracy

Chronotype and Social Jetlag Influence Performance and Injury during Reserve Officers’ Training Corps Physical Training

Sleep and circadian rhythms are critically important for optimal physical performance and maintaining health during training. Chronotype and altered sleep may modulate the response to exercise training, especially when performed at specific times/days, which may contribute to musculoskeletal injury. The purpose of this study was to determine if cadet characteristics (chronotype, sleep duration, and social jetlag) were associated with injury incidence and inflammation during physical training. Reserve Officers’ Training Corps (ROTC) cadets (n = 42) completed the Morningness/Eveningness Questionnaire to determine chronotype, and 1-week sleep logs to determine sleep duration and social jetlag. Salivary IL-6 was measured before and after the first and fourth exercise sessions during training. Prospective injury incidence was monitored over 14 weeks of training, and Army Physical Fitness Test scores were recorded at the conclusion. Chronotype, sleep duration, and social jetlag were assessed as independent factors impacting IL-6, injury incidence, and APFT scores using ANOVAs, chi-squared tests, and the t-test where appropriate, with significance accepted at p \u3c 0.05. Evening chronotypes performed worse on the APFT (evening = 103.8 ± 59.8 vs. intermediate = 221.9 ± 40.3 vs. morning = 216.6 ± 43.6; p \u3c 0.05), with no difference in injury incidence. Sleep duration did not significantly impact APFT score or injury incidence. Social jetlag was significantly higher in injured vs. uninjured cadets (2:40 ± 1:03 vs. 1:32 ± 55, p \u3c 0.05). Exercise increased salivary IL-6, with no significant effects of chronotype, sleep duration, or social jetlag. Evening chronotypes and cadets with social jetlag display hampered performance during morning APFT. Social jetlag may be a behavioral biomarker for musculoskeletal injury risk, which requires further investigation

Why sequence all eukaryotes?

Life on Earth has evolved from initial simplicity to the astounding complexity we experience today. Bacteria and archaea have largely excelled in metabolic diversification, but eukaryotes additionally display abundant morphological innovation. How have these innovations come about and what constraints are there on the origins of novelty and the continuing maintenance of biodiversity on Earth? The history of life and the code for the working parts of cells and systems are written in the genome. The Earth BioGenome Project has proposed that the genomes of all extant, named eukaryotes-about 2 million species-should be sequenced to high quality to produce a digital library of life on Earth, beginning with strategic phylogenetic, ecological, and high-impact priorities. Here we discuss why we should sequence all eukaryotic species, not just a representative few scattered across the many branches of the tree of life. We suggest that many questions of evolutionary and ecological significance will only be addressable when whole-genome data representing divergences at all of the branchings in the tree of life or all species in natural ecosystems are available. We envisage that a genomic tree of life will foster understanding of the ongoing processes of speciation, adaptation, and organismal dependencies within entire ecosystems. These explorations will resolve long-standing problems in phylogenetics, evolution, ecology, conservation, agriculture, bioindustry, and medicine

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Virological failure and development of new resistance mutations according to CD4 count at combination antiretroviral therapy initiation

Objectives: No randomized controlled trials have yet reported an individual patient benefit of initiating combination antiretroviral therapy (cART) at CD4 counts > 350 cells/μL. It is hypothesized that earlier initiation of cART in asymptomatic and otherwise healthy individuals may lead to poorer adherence and subsequently higher rates of resistance development. Methods: In a large cohort of HIV-positive individuals, we investigated the emergence of new resistance mutations upon virological treatment failure according to the CD4 count at the initiation of cART. Results: Of 7918 included individuals, 6514 (82.3%), 996 (12.6%) and 408 (5.2%) started cART with a CD4 count ≤ 350, 351-499 and ≥ 500 cells/μL, respectively. Virological rebound occurred while on cART in 488 (7.5%), 46 (4.6%) and 30 (7.4%) with a baseline CD4 count ≤ 350, 351-499 and ≥ 500 cells/μL, respectively. Only four (13.0%) individuals with a baseline CD4 count > 350 cells/μL in receipt of a resistance test at viral load rebound were found to have developed new resistance mutations. This compared to 107 (41.2%) of those with virological failure who had initiated cART with a CD4 count < 350 cells/μL. Conclusions: We found no evidence of increased rates of resistance development when cART was initiated at CD4 counts above 350 cells/μL. HIV Medicin

Reliability and Validation of the Hexoskin Wearable Bio-Collection Device During Walking Conditions

International Journal of Exercise Science 11(7): 806-816, 2018. To evaluate if the Hexoskin smart shirt (HxS) would produce valid and reliable measurements for heart rate (HR), respiratory rate (RR), minute ventilation (VE), step count (SC), and energy expenditure (EE) when compared to a Polar T-31 heart rate monitor, an Applied Electrochemistry Moxus Metabolic System, and a manual step count. A two-day walking treadmill protocol with participants walking for 3 minutes at 3 speeds (1.5mph, 2.5mph, 3.5mph, 0% grade) was performed. Forty-nine volunteers participated the first day, forty-six on the second, thirty-one were used for reliability. Values calculated for the HxS data used Pearson’s product-moment correlation (p \u3c 0.05; r ≥ 0.70) for validity and Cronbach’s a (≥ 0.70) for reliability. HxS HR (1.5mph; p\u3c0.01, r=0.86, a=0.86. 2.5mph; p\u3c0.01, r=0.81, a=0.88. 3.5mph; p\u3c0.01, r=0.85, a=0.85), HxS RR (1.5mph; p\u3c0.01, r=0.87, a=0.93. 2.5mph; p\u3c0.01, r=0.86, a=0.92. 3.5mph; p\u3c0.01, r=0.71, a=0.76), HxS VE (1.5mph; p=0.66, r=0.11, a=0.70. 2.5mph; p=0.01, r=0.15, a=0.73. 3.5mph; p=0.31, r=0.08, a=0.14), HxS SC (1.5mph; p=0.90, r=-0.01, a=0.70. 2.5mph; p=0.22, r=0.13, a=0.86. 3.5mph; p\u3c0.01, r=0.74, a=0.85), HxS EE (1.5mph; p\u3c0.01, r=0.56, a=0.85. 2.5mph; p\u3c0.01, r=0.50, a=0.83. 3.5mph; p\u3c0.01, r=0.51, a=0.80). HxS HR and RR provided valid and reliable measures at all three speeds while VE, SC, and EE had a mixture of results based on speed. These results are important in the use of the Hexoskin in an accurate manner for athletes, coaches, and for the potential medical applications being advocated in the field of telemedicine procedures

Oral versus Nasal Breathing during Moderate to High Intensity Submaximal Aerobic Exercise

Introduction: When comparing oral breathing versus nasal breathing, a greater volume of air can be transported through the oral passageway but nasal breathing may also have benefits at submaximal exercise intensities. Purpose: The purpose of this study was to determine breathing efficiency during increasing levels of submaximal aerobic exercise. Methods: Nineteen individuals (males N=9, females N=10) completed a test for maximal oxygen consumption (VO2max) and on separate days 4-min treadmill runs at increasing submaximal intensities (50%, 65%, and 80% of VO2max) under conditions of oral breathing or nasal breathing. Respiratory (respiration rate [RR], pulmonary ventilation [VE]), metabolic (oxygen consumption [VO2], carbon dioxide production [VCO2]) and efficiency measures (ventilatory equivalents for oxygen [Veq×O2-1] and carbon dioxide [Veq×CO2-1] were obtained. Data were analyzed utilizing a 2 (sex) x 2 (condition) x3 (intensity) repeated measures ANOVA with significance accepted at p≤0.05. Results: Significant interactions existed between breathing mode and intensity such that oral breathing resulted in greater RR, VE, VO2, and VCO2 at all three submaximal intensities (p<.05).  Veq×O2-1 and Veq×CO2-1 presented findings that nasal breathing was more efficient than oral breathing during the 65% and 80% VO2max intensities (p<0.05). Conclusion: Based on this analysis, oral breathing provides greater respiratory and metabolic volumes during moderate and moderate-to-high submaximal exercise intensities, but may not translate to greater respiratory efficiency. However when all variables are considered together, it is likely that oral breathing represents the more efficient mode, particularly at higher exercise intensities

Chronotype and Social Jetlag Influence Performance and Injury during Reserve Officers&rsquo; Training Corps Physical Training

Sleep and circadian rhythms are critically important for optimal physical performance and maintaining health during training. Chronotype and altered sleep may modulate the response to exercise training, especially when performed at specific times/days, which may contribute to musculoskeletal injury. The purpose of this study was to determine if cadet characteristics (chronotype, sleep duration, and social jetlag) were associated with injury incidence and inflammation during physical training. Reserve Officers&rsquo; Training Corps (ROTC) cadets (n = 42) completed the Morningness/Eveningness Questionnaire to determine chronotype, and 1-week sleep logs to determine sleep duration and social jetlag. Salivary IL-6 was measured before and after the first and fourth exercise sessions during training. Prospective injury incidence was monitored over 14 weeks of training, and Army Physical Fitness Test scores were recorded at the conclusion. Chronotype, sleep duration, and social jetlag were assessed as independent factors impacting IL-6, injury incidence, and APFT scores using ANOVAs, chi-squared tests, and the t-test where appropriate, with significance accepted at p &lt; 0.05. Evening chronotypes performed worse on the APFT (evening = 103.8 &plusmn; 59.8 vs. intermediate = 221.9 &plusmn; 40.3 vs. morning = 216.6 &plusmn; 43.6; p &lt; 0.05), with no difference in injury incidence. Sleep duration did not significantly impact APFT score or injury incidence. Social jetlag was significantly higher in injured vs. uninjured cadets (2:40 &plusmn; 1:03 vs. 1:32 &plusmn; 55, p &lt; 0.05). Exercise increased salivary IL-6, with no significant effects of chronotype, sleep duration, or social jetlag. Evening chronotypes and cadets with social jetlag display hampered performance during morning APFT. Social jetlag may be a behavioral biomarker for musculoskeletal injury risk, which requires further investigation

Moderate Intensity Resistance Training Significantly Elevates Testosterone following Upper Body and Lower Body Bouts When Total Volume is Held Constant

Introduction: It is unknown whether resistance training intensity or total volume of work affects the acute testosterone response to a greater extent. Purpose: Therefore, the circulating testosterone response was investigated following four resistance training protocols where total volume of work was held constant: moderate intensity (70% 1RM) upper body (bench press, bent barbell row, and military press), moderate intensity lower body (squat and deadlift), high intensity (90% 1RM) upper body, high intensity lower body. Methods: Total volume of work performed by each participant between protocols was maintained by adjusting the number of sets and or repetitions performed. Ten healthy, resistance trained men volunteered, and performed exercise protocols on separate days in a counterbalanced order. Capillary blood was obtained via finger stick at baseline (pre), immediately following the exercise session (post), and 1h post for the determination of testosterone concentration. Data were analyzed using a factorial ANOVA and significance was accepted at p≤ 0.05. Results: Both moderate intensity resistance protocols (upper and lower body) significantly increased testosterone concentration (p=0.026, and p=0.024 respectively), whereas the high intensity protocols elevated testosterone but failed to achieve significance (upper p=0.272, lower p=0.658). No difference was noted in post session testosterone concentration between upper and lower body protocols for either moderate (p=0.248) or high intensity (p=0.990). Conclusion: This may be useful for novice resistance trained individuals because it provides evidence that moderate intensity is sufficient to increase testosterone compared to high intensity protocols that could be associated with a greater risk of injury.Keywords: hormone response, equal total work, high intensity protoco