Effects of Exercise Training on Autonomic Function in Chronic Heart Failure: Systematic Review

Table 2

Overview of included randomized control trials ().

Study	Participants	Intervention	Outcome measures	Main results
Myers et al., 2007 [23]	CHF (EF < 40%); Ex: men, aged 56 ± 5 years; Con: men, aged 55 ± 7 years	Exercise: supervised hospital-based exercise training 1-hour walking and 45 min cycling, 5x/wk for 8 weeks at 60%–80% of heart rate reserve; Control: usual care		Exercise group got significant improvements in
Yaylali et al., 2015 [24]	CHF (EF < 45%, NYHA II-III); Interval: men, 4 women, aged 63.7 ± 8.8 years; Continuous: men, aged 59.6 ± 6.8 years; Con: men, 2 women, aged 60.6 ± 9.9 years	Exercise 1 (interval training): 30 minutes of cycle ergometer aerobic exercise 3x/wk for 12 weeks at 50%–75% HRR; Exercise 2 (continuous training): exercise protocol similar to interval training group without resting intervals; Control: continued with ADL	HRR1, HRR2	Interval training group got significant improvements in HRR2.; Unchanged HRR1 irrespective of any groups
Selig et al., 2004 [25]	CHF (EF < 40%, NYHA II-III); Ex: men, 4 women, aged 65 ± 13 years; Con: men, 2 women, aged 64 ± 9 years	Exercise: supervised hospital-based 1-hour multistation hydraulic moderate intensity (according to heart rate monitoring) resistance training, 3x/wk for 3 months; Control: usual care	Short-run rest ECG HRV: RR interval, SDNN, RMSSD, , , and LF/HF	Exercise group got significant decreases in LF, HF, and LF/HF after training
Murad et al., 2012 [26]	CHF (EF < 40%, NYHA II-III); Ex: men, 20 women, aged 68.0 ± 4.8 years; Con: men, 22 women, aged 70.1 ± 5.6 years	Exercise: supervised hospital-based 1-hour walking and 15–20 minutes of cycling exercise training, 3x/wk for 16 weeks at 40%–50% to 60%–70% heart rate reserve; Control: monitored with phone calls every 2 weeks	Short-run rest ECG HRV: SDNN, RMSSD	Exercise group showed significant increases in SDNN and RMSSD compared to controls
Ricca-Mallada et al., 2012 [27]	CHF (EF ≦ 40%, NYHA I-II); Ex: men, 2 women, aged 59.0 ± 7.9 years; Con: men, 2 women, aged 56.5 ± 8.4 years	Exercise: supervised hospital-based 55-minute circuit bicycle resistance training, 3x/wk for 24 weeks at 50%–80% of HR reserve; Control: usual medication	Short-run rest ECG HRV: RR interval, SDNN, LF, HF, and LF/HF	Exercise group got significant increases of mean RR interval, HF, and LF after training
Kilavuori et al., 1995 [28]	CHF (EF < 40%, NYHA II-III); Ex: men, aged 52 ± 8 years; Con: men, 1 woman, aged 52 ± 10 years	Exercise: supervised hospital-based ergometer cycling for 30 minutes, 3x/wk for 3 months at 50%–60% of; Control: no changing normal ADL	20 h Holter HRV: HF, LF, VLF, LF/HF, and VLF/HF	Exercise group got significant changes in HF, VLF/HF, and LF/HF during the day
Yeh et al., 2008 [29]	CHF (EF ≦ 40%, NYHA I–IV); Ex: men, 5 women, aged 66 ± 12 years; Con: men, 6 women, aged 61 ± 14 years	Exercise: supervised hospital-based Tai Chi training (1 hour), 2x/wk for 12 weeks; Control: usual care	24-hour Holter HRV: SDNN, RMSSD, pNN10–50, LF, HF, and LF/HF	Exercise group showed trends towards increased pNN10–50 values during sleep, but not in the control group
Cider et al., 1997 [30]	CHF (NYHA II-III); Ex: men, 12 women, aged 61.8 ± 9.8 years; Con: men, 12 women, aged 64.7 ± 5.3 years	Exercise: supervised hospital-based 60-minute circuit weight training at 60% 1-RM for 2 sets, 2x/week for 20 weeks; Control: usual care	24-hour Holter HRV: time/frequency domain parameters	No significant difference between the two groups in all HRV parameters

ADL: activities of daily living; CHF: chronic heart failure; ECG: electrocardiogram; EF: ejection fraction; HRR: heart rate recovery; HRV: heart rate variability; NYHA: New York Heart Association; pNN10–50: percentage difference between adjacent NN intervals that are greater than 10–50 ms; SDNN: standard deviation of all RR intervals; RMSSD: root mean square of difference in RR intervals; LF: low frequency; HF: high frequency; VLF: very-low frequency; : maximal oxygen consumption.