Changes in Physical Fitness After 12 Weeks of Structured Concurrent Exercise Training, High Intensity Interval Training, or Whole-Body Electromyostimulation Training in Sedentary Middle-Aged Adults: A Randomized Controlled Trial

Abstract

This study aimed to investigate the influence of different exercise training modalities [(i) a concurrent training based on physical activity recommendation from the World Health Organization group (PAR group), (ii) a high intensity interval training group (HIIT group), and (iii) a high intensity interval training adding whole-body electromyostimulation group (WB-EMS group)] on physical fitness in sedentary middle-aged adults. A total of 89 (52.7% women) middle-aged sedentary adults (53.7 ± 5.1 years old) were enrolled in the FIT-AGING study. Cardiorespiratory fitness was determined by a maximum treadmill test using indirect calorimetry. Lower, upper, and core body muscular strength were assessed by an isokinetic strength test, by the handgrip strength test, and by several core strength endurance tests, respectively. All the exercise types induced similar increases on cardiorespiratory fitness (Δ VO₂max ≥ 11%, Δ maximal heart rate ≥ 8%, and Δ total test duration ≥ 14%; all P ≤ 0.034), as well as on muscular strength (Δ extension and flexion peak torque ≥ 10%, Δ total hand grip ≥ 3%, Δ core strength endurance tests ≥ 20%; all P ≤ 0.050) compared with a control group. In conclusion, our results suggest that a 12-week structured exercise intervention improves physical fitness regardless of the training program in sedentary middle-aged adults. Despite slightly greater improvements in some physical fitness variables, the changes observed in the WB-EMS group were not superior to the other exercise programs.

Keywords: HIIT; VO2max; WB-EMS; cardiorespiratory fitness; muscular strength.

FIGURE 1

Flow-chart diagram. BMI, body mass index; CDV, cardiovascular; ECG, electrocardiogram; PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.

FIGURE 2

Changes in maximum oxygen uptake (VO₂max) in absolute (A) and relative terms (B), maximal heart rate (C), and total test duration (D) values before and after the intervention study. P-value [time, group, and interaction (time^∗group)] of repeated measures analysis of variance. ^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001 obtained by Student’s paired t-test. PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.

FIGURE 3

Changes in extension peak torque (A), flexion peak torque (B), and total hand grip (C) values before and after the intervention study. P-value [time, group, and interaction (time^∗group)] of repeated measures analysis of variance. ^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001 obtained by Student’s paired t-test. PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.

FIGURE 4

Changes in the trunk extensor isometric test (A), trunk flexor isometric test (B), side bridge test (C), and front plank test (D) values before and after the intervention study. P-value [time, group, and interaction (time^∗group)] of repeated measures analysis of variance. ^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001 obtained by Student’s paired t-test. PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.

FIGURE 5

Changes in maximum oxygen uptake (VO₂max) in absolute (A) and relative terms (B), maximal heart rate (C), and total test duration (D) after the intervention study among the four groups. Data are shown as means ± standard deviation. Parallel bars indicate significant differences between groups applying an analysis of covariance adjusting by baseline values, with post hoc Bonferroni-corrected t-test (^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001). PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.

FIGURE 6

Changes in extension peak torque (A), flexion peak torque (B), and total hand grip (C) after the intervention study among the four groups. Data are shown as means ± standard deviation. Parallel bars indicate significant differences between groups applying an analysis of covariance adjusting by baseline values, with post hoc Bonferroni-corrected t-test (^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001). PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.

FIGURE 7

Changes in the trunk extensor isometric test (A), trunk flexor isometric test (B), side bridge test (C), and front plank test (D) after the intervention study among the four groups. Data are shown as means ± standard deviation. Parallel bars indicate significant differences between groups applying an analysis of covariance adjusting by baseline values, with post hoc Bonferroni-corrected t-test (^∗P < 0.05, ^∗∗P < 0.01, ^∗∗∗P < 0.001). PAR, physical activity recommendations for adults proposed by the World Health Organization group; HIIT, high intensity interval training group; WB-EMS, whole-body electromyostimulation group.