Anthony S. Leicht

Heart Rate Variability and Endogenous Sex Hormones During the Menstrual Cycle in Young Women

To our knowledge, the relationship between all four endogenous female sex hormones and resting cardiac autonomic function has not been studied. The aim of the current study was to examine the association between the normal endogenous levels of oestrogen (17β‐oestradiol), progesterone, luteinising hormone and follicle‐stimulating hormone and heart rate variability (HRV) during the menstrual cycle in young eumenorrheic women. Ten healthy, young, female subjects volunteered for this study. HRV and endogenous hormone levels were recorded at three phases of the menstrual cycle: menses (day 3.8 ± 0.5), ovulation (day 15.8 ± 0.7) and luteal (day 22.1 ± 0.4) to ensure HRV recordings at times of low (menses) and high (ovulation and luteal) hormonal influence. Heart rate recordings were obtained from supine resting subjects and analysed on a Holter analysis system. Total power (TP, 0‐1.0 Hz), low frequency (LF, 0.041‐0.15 Hz), high frequency (HF, 0.15‐0.80 Hz) and LF/HF components of HRV were examined. Despite a significantly greater HR at ovulation and normal cyclic variations in all endogenous sex hormone levels, no measure of HRV was significantly different between menstrual cycle phases. Significant correlations between oestrogen levels and absolute measures of HRV at ovulation were identified. The results of the current study demonstrated that the normal cyclic variations in endogenous sex hormone levels during the menstrual cycle were not significantly associated with changes in cardiac autonomic control as measured by HRV. Significant correlation between peak oestrogen levels and HRV measures at ovulation provided further support for the reported cardioprotective effects of oestrogen in healthy females.

Effect of Ramipril on Walking Times and Quality of Life Among Patients With Peripheral Artery Disease and Intermittent Claudication: A Randomized Controlled Trial

IMPORTANCE Approximately one-third of patients with peripheral artery disease experience intermittent claudication, with consequent loss of quality of life. OBJECTIVE To determine the efficacy of ramipril for improving walking ability, patient-perceived walking performance, and quality of life in patients with claudication. DESIGN, SETTING, AND PATIENTS Randomized, double-blind, placebo-controlled trial conducted among 212 patients with peripheral artery disease (mean age, 65.5 [SD, 6.2] years), initiated in May 2008 and completed in August 2011 and conducted at 3 hospitals in Australia. INTERVENTION Patients were randomized to receive 10 mg/d of ramipril (n = 106) or matching placebo (n = 106) for 24 weeks. MAIN OUTCOME MEASURES Maximum and pain-free walking times were recorded during a standard treadmill test. The Walking Impairment Questionnaire (WIQ) and Short-Form 36 Health Survey (SF-36) were used to assess walking ability and quality of life, respectively. RESULTS At 6 months, relative to placebo, ramipril was associated with a 75-second (95% CI, 60-89 seconds) increase in mean pain-free walking time (P < .001) and a 255-second (95% CI, 215-295 seconds) increase in maximum walking time (P < .001). Relative to placebo, ramipril improved the WIQ median distance score by 13.8 (Hodges-Lehmann 95% CI, 12.2-15.5), speed score by 13.3 (95% CI, 11.9-15.2), and stair climbing score by 25.2 (95% CI, 25.1-29.4) (P < .001 for all). The overall SF-36 median Physical Component Summary score improved by 8.2 (Hodges-Lehmann 95% CI, 3.6-11.4; P = .02) in the ramipril group relative to placebo. Ramipril did not affect the overall SF-36 median Mental Component Summary score. CONCLUSIONS AND RELEVANCE Among patients with intermittent claudication, 24-week treatment with ramipril resulted in significant increases in pain-free and maximum treadmill walking times compared with placebo. This was associated with a significant increase in the physical functioning component of the SF-36 score. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00681226.

Effects of a long term exercise program on lower limb mobility, physiological responses, walking performance and physical activity levels in patients with peripheral arterial disease

OBJECTIVE The purpose of the study was to examine the effects of a 12-month exercise program on lower limb mobility (temporal-spatial gait parameters and gait kinematics), walking performance, peak physiological responses, and physical activity levels in individuals with symptoms of intermittent claudication due to peripheral arterial disease (PAD-IC). METHODS Participants (n = 21) with an appropriate history of PAD-IC, ankle-brachial pressure index (ABI) <0.9 in at least one leg and a positive Edinburgh claudication questionnaire response were prospectively recruited. Participants were randomly allocated to either a control PAD-IC group (CPAD-IC) (n = 11) that received standard medical therapy and a treatment PAD-IC group (TPAD-IC) (n = 10), which also took part in a 12-month supervised exercise program. A further group of participants (n = 11) free of PAD (ABI >0.9) and who were non-regular exercisers were recruited from the community to act as age and mass matched controls (CON). Lower limb mobility was determined via two-dimensional video motion analysis. A graded treadmill test was used to assess walking performance and peak physiological responses to exercise. Physical activity levels were measured via a 7-day pedometer recording. Differences between groups were analyzed via repeated measures analysis of variance (ANOVA). RESULTS The 12-month supervised exercise program had no significant effect on lower limb mobility, peak physiological responses, or physical activity levels in TPAD-IC compared with CPAD-IC participants. However, the TPAD-IC participants demonstrated significantly greater walking performance (171% improvement in pain free walking time and 120% improvement in maximal walking time compared with baseline). CONCLUSION The results of this study confirm that a 12-month supervised exercise program will result in improved walking performance, but does not have an impact on lower limb mobility, peak physiological responses, or physical activity levels of PAD-IC patients.

Seasonal Changes in Physical Performance and Heart Rate Variability in High Level Futsal Players

The aim of this study was to determine the changes in physical performance and resting heart rate variability (HRV) in professional futsal players during the pre-season and in-season training periods. 11 athletes took part in the study (age=24.3±2.9 years; height=176.3±5.2 cm; weight=76.1±6.3 kg), and performed a repeated-sprint ability (RSA) test [6×40 m (20+20 m with a 180° change of direction) sprints separated by 20 s of passive recovery] and Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) at 3 different moments (M1=beginning of pre-season; M2=end of pre-season; M3=mid in-season). The HRV indices were assessed at the same moments. After the short pre-season (3-week), mean RSA time (RSAmean) (M1=7.43±0.2 s; M2=7.24±0.2 s; P=0.003), decrement in RSA performance (RSAdecrement) (M1=6.7±0.3%; M2=5.0±0.9%; P=0.001), and Yo-Yo IR1 distance (M1=1.244±298 m; M2=1.491±396 m; P=0.002) were significantly improved (P<0.05). During the in-season (i. e., M3), performance in Yo-Yo IR1 and RSAmean were maintained. In contrast, RSAbest (M2=6.89±0.2 to M3=6.69±0.3; P=0.001) was improved and RSAdecrement (M2=5.0±0.9% to M3=6.6±0.9%; P=0.001) was impaired. At M2, there was an increase in HRV vagal-related indices compared with M1 that was maintained at M3. In conclusion, after a short pre-season, futsal players improved their RSA and Yo-Yo IR1 performance with concomitant improvements in HRV. These indices were maintained during the in-season period while RSAbest was improved and RSAdecrement impaired. Frequent monitoring of these performances and HRV indices may assist with identification of individual training adaptations and/or early signs of maladaption.

Influence of exercise intensity on systemic oxidative stress and antioxidant capacity.

The aim of the current study was to examine the influence of exercise intensity on systemic oxidative stress (OS) and endogenous antioxidant capacity. Non‐smoking, sedentary healthy adult males (n = 14) participated in two exercise sessions using an electronically braked cycle ergometer. The first session consisted of a graded exercise test to determine maximal power output and oxygen consumption (VO2max). One week later, participants undertook 5‐min cycling bouts at 40%, 55%, 70%, 85% and 100% of VO2max, with passive 12‐min rest between stages. Measures of systemic OS reactive oxygen metabolites (dROM), biological antioxidant potential (BAP), heart rate (HR), VO2, blood lactate and rating of perceived exertion were assessed at rest and immediately following each exercise stage. Significant (P<0·05) differences between exercise bouts were examined via repeated measures ANOVA and post hoc pairwise comparisons with Bonferroni correction. Increasing exercise intensity significantly augmented HR (P<0·001), VO2 (P<0·001), blood lactate (P<0·001) and perceived exertion (P<0·001) with no significant effect on dROM levels compared with resting values. In contrast, increasing exercise intensity resulted in significantly (P<0·01) greater BAP at 70% (2427 ± 106), 85% (2625 ± 121) and 100% (2651 ± 92) of VO2max compared with resting levels (2105 ± 57 μmol Fe2+/L). The current results indicate that brief, moderate‐to‐high‐intensity exercise significantly elevates endogenous antioxidant defences, possibly to counteract increased levels of exercise‐induced reactive oxygen species. Regular moderate‐to‐high‐intensity exercise may protect against chronic OS associated diseases via activation, and subsequent upregulation of the endogenous antioxidant defence system.

Evaluating the psychometric quality of social skills measures: a systematic review

Introduction Impairments in social functioning are associated with an array of adverse outcomes. Social skills measures are commonly used by health professionals to assess and plan the treatment of social skills difficulties. There is a need to comprehensively evaluate the quality of psychometric properties reported across these measures to guide assessment and treatment planning. Objective To conduct a systematic review of the literature on the psychometric properties of social skills and behaviours measures for both children and adults. Methods A systematic search was performed using four electronic databases: CINAHL, PsycINFO, Embase and Pubmed; the Health and Psychosocial Instruments database; and grey literature using PsycExtra and Google Scholar. The psychometric properties of the social skills measures were evaluated against the COSMIN taxonomy of measurement properties using pre-set psychometric criteria. Results Thirty-Six studies and nine manuals were included to assess the psychometric properties of thirteen social skills measures that met the inclusion criteria. Most measures obtained excellent overall methodological quality scores for internal consistency and reliability. However, eight measures did not report measurement error, nine measures did not report cross-cultural validity and eleven measures did not report criterion validity. Conclusions The overall quality of the psychometric properties of most measures was satisfactory. The SSBS-2, HCSBS and PKBS-2 were the three measures with the most robust evidence of sound psychometric quality in at least seven of the eight psychometric properties that were appraised. A universal working definition of social functioning as an overarching construct is recommended. There is a need for ongoing research in the area of the psychometric properties of social skills and behaviours instruments.

Effects of additional repeated sprint training during preseason on performance, heart rate variability, and stress symptoms in futsal players: a randomized controlled trial.

Abstract Soares-Caldeira, LF, de Souza, EA, de Freitas, VH, de Moraes, SMF, Leicht, AS, and Nakamura, FY. Effects of additional repeated sprint training during preseason on performance, heart rate variability, and stress symptoms in futsal players: A randomized controlled trial. J Strength Cond Res 28(10): 2815–2826, 2014—The aim of this study was to investigate whether supplementing regular preseason futsal training with weekly sessions of repeated sprints (RS) training would have positive effects on repeated sprint ability (RSA) and field test performance. Thirteen players from a professional futsal team (22.6 ± 6.7 years, 72.8 ± 8.7 kg, 173.2 ± 6.2 cm) were divided randomly into 2 groups (AddT: n = 6 and normal training group: n = 7). Both groups performed a RSA test, Yo-Yo intermittent recovery test level 1 (YoYo IR1), squat (SJ) and countermovement jumps (CMJ), body composition, and heart rate variability (HRV) measures at rest before and after 4 weeks of preseason training. Athletes weekly stress symptoms were recorded by psychometric responses using the Daily Analysis of Life Demands for Athletes questionnaire and subjective ratings of well-being scale, respectively. The daily training load (arbitrary units) was assessed using the session of rating perceived exertion method. After the preseason training, there were no significant changes for body composition, SJ, CMJ, and RSAbest. The YoYo IR1, RSAmean, RSAworst, and RSAdecreament were significantly improved for both groups (p ⩽ 0.05). The HRV parameters improved significantly within both groups (p ⩽ 0.05) except for high frequency (HF, absolute and normalized units, [n.u.]), low frequency (LF) (n.u.), and the LF/HF ratio. A moderate effect size for the AddT group was observed for resting heart rate and several HRV measures. Training load and psychometric responses were similar between both groups. Additional RS training resulted in slightly greater positive changes for vagal-related HRV with similar improvements in performance and training stress during the preseason training in futsal players.

Determinants of Endothelial Function in a Cohort of Patients with Peripheral Artery Disease

Objectives: Endothelial dysfunction assessed by brachial artery flow-mediated dilatation (FMD) has been associated with cardiovascular events. There have been relatively few studies examining FMD or other measures of endothelial function in patients with peripheral artery disease (PAD). The aim of this study was to examine determinants of FMD in a homogenous cohort of patients with PAD. Methods: We prospectively assessed patients presenting with life style-limiting intermittent claudication to establish the presence of cardiovascular risk factors, obesity and metabolic syndrome. Fasting serum was assayed for lipids, C-reactive protein, adiponectin, leptin, resistin and osteoprotegerin (OPG). FMD was measured by high-resolution ultrasound. Results: Serum concentrations of OPG were elevated in patients with obesity and metabolic syndrome. FMD was impaired in patients with obesity and metabolic syndrome and negatively correlated with serum concentrations of OPG. By multiple regression analysis, metabolic syndrome was independently associated with impaired FMD after adjustment for age, smoking, ischaemic heart disease, cerebrovascular disease and severity of PAD. Conclusions: Our findings suggest that metabolic syndrome is an important determinant of endothelial function in patients with PAD, and OPG may be a useful biomarker of this effect.

Moderate-term reproducibility of heart rate variability during rest and light to moderate exercise in children

Previous studies have demonstrated the high reproducibility of heart rate variability (HRV) measures in adults while little information exists concerning HRV reproducibility in children. Subsequently, the aim of the current study was to examine the moderate-term reproducibility of heart rate and frequency domain measures of HRV during rest and light to moderate exercise in children. Ten healthy children (6 males, 4 females) aged between 7 and 12 years of age volunteered for this study with HRV recordings obtained during supine rest and three treadmill walking exercise work rates (< or =60% maximum heart rate), initially and then 8 weeks later. Differences (P < 0.05) between variables were examined using paired t-tests or Wilcoxon signed rank tests while reliability and reproducibility were examined by intraclass correlation coefficients (ICC), coefficients of variation (CV), and mean bias ratio and ratio limits of agreement (LOA). Heart rate and all measures of HRV at rest and exercise were unchanged after 8 weeks. Significant ICC were documented primarily during rest (0.72-0.85) while weaker relationships (-0.02-0.87) were evident during exercise. A large range of CV was identified during rest (6-33%) and exercise (3-128%) while the ratio LOA were variable and substantial (1.04-2.73). Despite similar HRV over an 8-week period, variable ICC and sizable CV and ratio LOA indicate moderate to poor reproducibility of HRV in children, particularly during light to moderate exercise. Studies examining HRV in children should include age- or maturation stage-matched control participants to address the age-related change in HRV and inadequate HRV reliability.

Influence of postexercise cooling techniques on heart rate variability in men.

The reduction of core body temperature (TC) is vitally important in the treatment of hyperthermia; however, little is known regarding the impact of cooling treatments on the autonomic control of heart rate (HR). The aim of the present study was to examine the influence of three field‐based hyperthermia treatments on the neural control of HR via heart rate variability (HRV). Following exercise‐induced hyperthermia (TC∼40.0°C) in a warm environment (34.2 ± 0.5°C), nine healthy, active men were treated during recovery, in a randomized order, with intravenous cold saline infusion (IV) or ice packs (ICE) or fan cooling with intermittent water spray (FAN) for 40 min. During each treatment, HR dynamics via power spectral (VLF, LF, HF), Poincare plot (SD1, SD2), approximate entropy (ApEn) and short‐ (α1) and long‐term (α2) fractal scaling analyses were determined every 10 min. At recovery onset, HR and TC were similar between treatments and were significantly reduced over the 40 min recovery period. During recovery, HR and α2 were significantly reduced from initial levels but were significantly greater for IV compared with ICE and FAN. In contrast, VLF, LF, HF, SD1, SD2 and ApEn increased during recovery, with all being significantly lower for IV compared with ICE and/or FAN. The present results demonstrated that IV, compared with ICE and FAN, resulted in significantly greater HR, reduced spectral and geometrical HRV, lower HR complexity and reduced long‐term HR control, indicative of reduced vagal and/or increased sympathetic modulation. Specific treatments for exercise‐induced hyperthermia may result in an altered sympathovagal balance that requires further examination.