scholarly journals Heart Rate Dynamics During Acute Recovery From Maximal Aerobic Exercise in Young Adults

2021 ◽  
Vol 12 ◽  
Author(s):  
Nathaniel T. Berry ◽  
Emily Bechke ◽  
Lenka H. Shriver ◽  
Susan D. Calkins ◽  
Susan P. Keane ◽  
...  

IntroductionResting heart rate (HRrest), heart rate variability (HRV), and HR recovery (HRR) from exercise provide valuable information about cardiac autonomic control. RR-intervals during acute recovery from exercise (RRrec) are commonly excluded from HRV analyses due to issues of non-stationarity. However, the variability and complexity within these trends may provide valuable information about changes in HR dynamics.PurposeAssess the complexity of RRrec and determine what physiologic and demographic information are associated with differences in these indices in young adults.MethodsRR-intervals were collected throughout maximal treadmill exercise and recovery in young adults (n = 92). The first 5 min of RRrec were (1) analyzed with previously reported methods that use 3-interval lengths for comparison and (2) detrended using both differencing(diff) and polynomial regression(res). The standard deviation of the normal interval (SDNN), root mean square of successive differences (rMSSD), root mean square (RMS) of the residual of regression, and sample entropy (SampEn) were calculated. Repeated measures analysis of covariance (ANCOVA) tested for differences in these indices for each of the methodological approaches, controlling for race, body fat, peak oxygen uptake (VO2peak), and resting HR (HRrest). Statistical significance was set at p < 0.05.ResultsVO2peak and HRrest were significantly correlated with traditional measures of HRR and the variability surrounding RRrec. SampEndiff and SampEnres were correlated with VO2peak but not HRrest or HRR. The residual-method provided a significantly (p = 0.04) lower mean standard error (MSE) (0.064 ± 0.042) compared to the differencing-method (0.100 ± 0.033).ConclusionsComplexity analysis of RRrec provides unique information about cardiac autonomic regulation immediately following the cessation of exercise when compared to traditional measures of HRR and both HRrest and VO2peak influence these results.

Life ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 343
Author(s):  
Carlos Ruiz-Moreno ◽  
Beatriz Lara ◽  
Jorge Gutiérrez-Hellín ◽  
Jaime González-García ◽  
Juan Del Coso

Pre-exercise caffeine ingestion has been shown to increase the workload at ventilatory threshold, suggesting an ergogenic effect of this stimulant on submaximal aerobic exercise. However, the time course of tolerance to the effect of caffeine on ventilatory threshold is unknown. This study aimed to determine the evolution of tolerance to the ergogenic effect of caffeine on the ventilatory threshold. Methods: Eleven participants (age 32.3 ± 4.9 yrs, height 171 ± 8 cm, body mass 66.6 ± 13.6 kg, VO2max = 48.0 ± 3.8 mL/kg/min) took part in a longitudinal, double-blind, placebo-controlled, randomized, crossover experimental design. Each participant took part in two identical treatments: in one treatment, participants ingested a capsule containing 3 mg of caffeine per kg of body mass per day (mg/kg/day) for twenty consecutive days; in the other treatment, participants ingested a capsule filled with a placebo for the same duration and frequency. During these treatments, participants performed a maximal ramp test on a cycle ergometer three times per week and the second ventilatory threshold (VT2) was assessed by using the ventilatory equivalents for oxygen and carbon dioxide. Results: A two-way ANOVA with repeated measures (substance × time) revealed statistically significant main effects of caffeine (p < 0.01) and time (p = 0.04) on the wattage obtained at VT2, although there was no interaction (p = 0.09). In comparison to the placebo, caffeine increased the workload at VT2 on days 1, 4, 6 and 15 of ingestion (p < 0.05). The size of the ergogenic effect of caffeine over the placebo on the workload at VT2 was progressively reduced with the duration of the treatment. In addition, there were main effects of caffeine (p = 0.03) and time (p = 0.16) on VO2 obtained at VT2, with no interaction (p = 0.49). Specifically, caffeine increased oxygen uptake at VT2 on days 1 and 4 (p < 0.05), with no other caffeine–placebo differences afterwards. For heart rate obtained at VT2, there was a main effect of substance (p < 0.01), while the overall effect of time (p = 0.13) and the interaction (p = 0.22) did not reach statistical significance. Heart rate at VT2 was higher with caffeine than with the placebo on days 1 and 4 (p < 0.05). The size of the effect of caffeine on VO2 and heart at VT2 tended to decline over time. Conclusion: Pre-exercise intake of 3 mg/kg/day of caffeine for twenty days enhanced the wattage obtained at VT2 during cycling ramp tests for ~15 days of ingestion, while there was a progressive attenuation of the size of the ergogenic effect of caffeine on this performance variable. Therefore, habituation to caffeine through daily ingestion may reduce the ergogenic effect of this stimulant on aerobic exercise of submaximal intensity.


Animals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1867
Author(s):  
Michele Panzera ◽  
Daniela Alberghina ◽  
Alessandra Statelli

Background: Few studies have been performed to identify objective indicators for the selection of therapeutic donkeys or to assess their welfare during animal-assisted interventions (AAIs) Objective: This study aimed to evaluate the response to the ethological test and the modifications of physiological parameters in donkeys subjected to AAI sessions. Methods: Thirteen donkeys were subjected to a behavioral evaluation during an AAI session. Heart rate, heart rate variability, and root mean square of successive difference values were detected. Results: Statistically significant changes in the tested parameters were observed during AAI sessions. Conclusions: In donkeys, there was a neurovegetative involvement during AAI sessions. Our data give a contribution to the evaluation of donkey welfare during AAIs.


Hypertension ◽  
2020 ◽  
Vol 76 (4) ◽  
pp. 1256-1262
Author(s):  
Balewgizie S. Tegegne ◽  
Tengfei Man ◽  
Arie M. van Roon ◽  
Nigus G. Asefa ◽  
Harriëtte Riese ◽  
...  

Dysregulation of the cardiac autonomic nervous system, as indexed by reduced heart rate variability (HRV), has been associated with the development of high blood pressure (BP). However, the underlying pathological mechanisms are not yet fully understood. This study aimed to estimate heritability of HRV and BP and to determine their genetic overlap. We used baseline data of the 3-generation Lifelines population-based cohort study (n=149 067; mean age, 44.5). In-house software was used to calculate root mean square of successive differences and SD of normal-to-normal intervals as indices of HRV based on 10-second resting ECGs. BP was recorded with an automatic BP monitor. We estimated heritabilities and genetic correlations with variance components methods in ASReml software. We additionally estimated genetic correlations with bivariate linkage disequilibrium score regression using publicly available genome-wide association study data. The heritability (SE) estimates were 15.6% (0.90%) for SD of normal-to-normal intervals and 17.9% (0.90%) for root mean square of successive differences. For BP measures, they ranged from 24.4% (0.90%) for pulse pressure to 30.3% (0.90%) for diastolic BP. Significant negative genetic correlations (all P <0.0001) of root mean square of successive differences/SD of normal-to-normal intervals with systolic BP (−0.20/−0.16) and with diastolic BP (−0.15/−0.13) were observed. LD score regression showed largely consistent genetic correlation estimates of root mean square of successive differences/SD of normal-to-normal intervals with systolic BP (range, −0.08 to −0.23) and diastolic BP (range, −0.20 to −0.27). Our study shows a substantial contribution of genetic factors in explaining the variance of HRV and BP measures in the general population. The significant negative genetic correlations between HRV and BP indicate that genetic pathways for HRV and BP partially overlap.


2016 ◽  
Vol 41 (10) ◽  
pp. 1077-1082 ◽  
Author(s):  
James M. Green ◽  
Alyssa Olenick ◽  
Caroline Eastep ◽  
Lee Winchester

Caffeine (CAF) blunts estimated ratings of perceived exertion (RPE) but the effects on RPE production are unclear. This study examined effects of acute caffeine ingestion during treadmill exercise where participants exercised at prescribed RPE 4 and 7. Recreational runners (maximal oxygen consumption = 51.4 ± 9.8 mL·kg−1·min−1) (n = 16) completed a maximal treadmill test followed by trials where they selected treadmill velocity (VEL) (1% grade) to produce RPE 4 and RPE 7 (10 min each). RPE production trials followed CAF (6 mg·kg−1) or placebo (PLA) (counterbalanced) ingestion. Participants were blinded to treadmill VEL but the Omni RPE scale was in full view. Repeated-measures ANOVA showed a main effect (trial) for VEL (CAF ∼5 m·min−1 faster) for RPE 4 (p = 0.07) and RPE 7 (p = 0.03). Mean heart rate and oxygen consumption responses were consistently higher for CAF but failed to reach statistical significance. Individual responses to CAF were labeled positive using a criterion of 13.4 m·min−1 faster for CAF (vs. PLA). Ten of 32 trials (31%) were positive responses. In these, systematic increases were observed for heart rate (∼12 beats·min−1) and oxygen consumption (∼5.7 mL·kg−1·min−1). Blunted/stable respiratory exchange ratio values at higher VEL for positive responders suggest increased free fatty acid reliance during CAF. In conlusion, mean results show a mild effect of CAF during RPE production. However, individual responses more clearly indicate whether a true effect is possible. Trainers and individuals should consider individual responses to ensure effectively intensity regulation.


Author(s):  
Chantelle A. Nielson ◽  
Emily G. Deegan ◽  
Aaron S.L. Hung ◽  
Abraham J Nunes

The purpose of this study was to compare the effects of sleep deprivation and rest on postural control. It was hypothesized that significant increases in COP deviations will occur after sleep deprivation. Methods. Four healthy adults (age= 21.50 years; mass= 68.93 kg) participated in two protocols involving sleep and sleep-deprivation. Within each condition multiple 40s impairments of visual, somatosensory, and/or vestibular sensory feedback were performed. Balance was quantified using root-mean-square (RMS) of the centre of pressure (COP) and COP Variance. Results. Two-way ANOVA demonstrated no significant effect of sleep deprivation on balance between sensory insults. Paired t-tests were performed nonetheless and revealed significant differences within the sleep-deprived condition. COP RMS and Variance were significantly greater medio-laterally with all systems impaired (ALL) (3.43 ± 0.63 mm, p


Stroke ◽  
2021 ◽  
Author(s):  
Galit Weinstein ◽  
Kendra Davis-Plourde ◽  
Alexa S. Beiser ◽  
Sudha Seshadri

Background and Purpose: The autonomic nervous system has been implicated in stroke and dementia pathophysiology. High resting heart rate and low heart rate variability indicate the effect of autonomic imbalance on the heart. We examined the associations of resting heart rate and heart rate variability with incident stroke and dementia in a community-based cohort of middle- and old-aged adults. Methods: The study sample included 1581 participants aged >60 years and 3271 participants aged >45 years evaluated for incident dementia and stroke, respectively, who participated in the Framingham Offspring cohort third (1983–1987) examination and had follow-up for neurology events after the seventh (1998–2001) examination. Heart rate variability was assessed through the standard deviation (SD) of normal-to-normal RR intervals and the root mean square of successive differences between normal heartbeats from 2-hour Holter monitor. Participants were followed-up for stroke and dementia incidence from exam 7 to a maximum of 10 years. Cox regression models were used to assess the link of resting heart rate and heart rate variability with stroke and dementia risk while adjusting for potential confounders, and interactions with age and sex were assessed. Results: Of the dementia (mean age, 55±6 years, 46% men) and stroke (mean age, 48±9 years, 46% men) samples, 133 and 127 developed dementia and stroke, respectively, during the follow-up. Overall, autonomic imbalance was not associated with dementia risk. However, age modified the associations such that SD of normal-to-normal intervals and root mean square of successive differences were associated with dementia risk in older people (hazard ratio [HR] [95% CI] per 1SD, 0.61 [0.38–0.99] and HR [95% CI] per 1SD, 0.34 [0.15–0.74], respectively). High resting heart rate was associated with increased stroke risk (HR [95% CI] per 10 bpm, 1.18 [1.01–1.39]), and high SD of normal-to-normal intervals was associated with lower stroke risk in men (HR [95% CI] per 1SD, 0.46 [0.26–0.79]) but not women (HR [95% CI] per 1SD, 1.25 [0.88–1.79]; P for interaction=0.003). Conclusions: Some measures of cardiac autonomic imbalance may precede dementia and stroke occurrence, particularly in older ages and men, respectively.


2005 ◽  
Vol 42 (2) ◽  
pp. 246-252 ◽  
Author(s):  
Gary G. Berntson ◽  
David L. Lozano ◽  
Yun-Ju Chen

2001 ◽  
Vol 16 (1) ◽  
pp. 16-20 ◽  
Author(s):  
Linda S. Pescatello ◽  
Donna Murphy ◽  
Jeannine Vollono ◽  
Elizabeth Lynch ◽  
James Bernene ◽  
...  

Purpose. We examined the cardiovascular health profiles of benefit-eligible hospital employees who participated in an incentive screen program for 4 years. We also determined if cardiovascular health changes differed between participants (CHAP) who enrolled in structured follow-up risk reduction programs (CHAPplus) compared with those who chose less formal options (CHAPonly). Methods. CHAP consisted of cardiovascular screens, results counseling, and encouragement to participate in education and behavioral support programs. After adjusting for gender, medication use, and baseline levels of adiposity and physical activity, cardiovascular health changes were tested with repeated-measures analysis of covariance (ANCOVA) among CHAP participants and by CHAP type. Results. CHAP 4-year members (n = 278) were generally healthy and mostly women (87%) with an average age of 40.6 ± .5 years at baseline. Despite increases in overall (p = .034) and central adiposity (p = .001), cardiovascular health improvements were found for the total cholesterol/high-density lipoprotein ratio (TCHOL/HDL; p = .007), low-density lipoprotein (p = .009), and blood glucose (p = .018) among 4-year CHAP members. CHAPonly employees showed greater improvements in most cardiovascular health indicators than CHAPplus participants, although these differences did not achieve statistical significance. Discussion. Cardiovascular health improvements were associated with long-term participation in a hospital worksite incentive screen program. The cardiovascular health benefits tended to be greatest for CHAP employees who chose informal follow-up risk reduction options (CHAPonly) than those who enrolled in structured programs (CHAPplus).


Sign in / Sign up

Export Citation Format

Share Document