Improvement of heart rate variability after exercise training and its predictors in COPD

Endurance-trained athletes have increased heart rate variability (HRV), but it is not known whether exercise training improves the HRV and baroreflex sensitivity (BRS) in sedentary persons. We compared the effects of low- and high-intensity endurance training on resting heart rate, HRV, and BRS. The maximal oxygen uptake and endurance time increased significantly in the high-intensity group compared with the control group. Heart rate did not change significantly in the low-intensity group but decreased significantly in the high-intensity group (−6 beats/min, 95% confidence interval; −10 to −1 beats/min, exercise vs. control). No significant changes occurred in either the time or frequency domain measures of HRV or BRS in either of the exercise groups. Exercise training was not able to modify the cardiac vagal outflow in sedentary, middle-aged persons.

Download Full-text

Comparison of Linear and Nonlinear HRV Dynamics Across Exercise Intensities After Menopause

Journal of Aging and Physical Activity ◽

10.1123/japa.2018-0407 ◽

2020 ◽

Vol 28 (1) ◽

pp. 149-154

Author(s):

Julia C. Orri ◽

Elizabeth M. Hughes ◽

Deepa G. Mistry ◽

Antone Scala

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Exercise Training ◽

Postmenopausal Women ◽

Maximal Exercise ◽

Exercise Recovery ◽

Active Recovery ◽

Vigorous Exercise ◽

Main Effect ◽

Linear And Nonlinear

The authors compared the linear and nonlinear heart rate variability dynamics from rest through maximal exercise in postmenopausal women who trained at either moderate or high intensities. The outcome variables included the RR triangular index, TINN, SD1, SD2, SD1/SD2, DFA α1, DFA α2, and α1/α2. Maximal exercise reduced SD1, SD2, DFA α1, DFA α2, α1/α2, RRTri, and TINN in both groups and increased SD1/SD2 (p < .05). Two minutes of active recovery produced significant increases in SD1, SD2, DFA α1, and TINN, compared with exercise in both groups (p < .0001). There was also a significant main effect between groups for RRTri during exercise recovery, with the moderate group achieving higher levels (p < .04). The authors have shown that both moderate and vigorous exercise training can lead to a healthy response to maximal exercise and recovery, with the moderate group having a slightly improved recovery in the triangular index.

Download Full-text

Determination of minimal recording period to assess resting heart rate variability during pregnancy

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2019-0351 ◽

2020 ◽

Vol 45 (4) ◽

pp. 431-436

Author(s):

Danilo Fernandes da Silva ◽

Shuhiba Mohammad ◽

Kelly Ann Hutchinson ◽

Kristi Bree Adamo

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Exercise Training ◽

Pregnant Women ◽

Resting Heart Rate ◽

Time Segment ◽

Natural Logarithm ◽

Resting Heart Rate Variability ◽

Measurement Period

Traditionally, resting heart rate variability (rHRV) is measured for 10 min using the last 5 min for analyses (e.g., criterion period). It is unknown whether the measurement period can be shortened in pregnant women as there are currently no established standards. We aimed to compare shorter time segments (e.g., from the 1st to 10th minutes) of the parasympathetic index natural logarithm transformation of root mean square of successive R–R differences (Ln rMSSD) with the criterion period in pregnant and nonpregnant women. Twelve pregnant (age: 30.8 ± 3.4 years; gestational age: 20.1 ± 5.0 weeks) and 15 nonpregnant women (age: 29.8 ± 4.0 years) were included. rHRV was measured using a portable heart rate monitor for 10 min while sitting. Ln rMSSD difference/agreement between shorter time segments and criterion period was analyzed. The result observed between the 4th–5th minutes was the shortest time segment not different from/highly agreed with the criterion period in pregnant women (difference [95% confidence interval (CI)]: −0.10 [−0.22 to 0.02]/bias ± 1.96 × SD: −0.06 [−0.38 to 0.25]). In nonpregnant women, the 2nd–3rd-minute segment was the shortest with similar results (difference [95% CI]: −0.04 [−0.15 to 0.07]/bias ± 1.96 × SD: −0.03 [−0.39 to 0.32]). The Ln rMSSD was found to be stable from the 5th–10th minutes and the 3rd–10th minutes in pregnant and nonpregnant women, respectively. A shortened rHRV assessment can increase its applicability in clinical/exercise-training settings. Novelty Ln rMSSD can be measured for 5 min in pregnant women, with the last 1-min segment analyzed. The last 1-min segment from 3 min can be used for rHRV measurement in nonpregnant women. The shortened rHRV assessment can facilitate its applicability in clinical/exercise-training settings.

Download Full-text