The effect of high intensity combined training on functional capacity, muscle strength, body composition, agility and dynamic balance in patients with coronary artery disease
Authors: Resnik M , Corsi M , Moreno G , Taurozzi S , Puga L , Esker L , Peralta L , Bianconi M , Zivano D 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
There is still controversy regarding the exercise characteristics that are more effective for improving peak oxygen uptake (VO2 peak), cardiac and metabolic function. High- intensity interval exercise training (HIIT) has been shown to elicit comparable and/or superior performance on endurance capacity (EC), ventricular function (VF) and quality of life. By other side, there is robust evidence that combined endurance and strength training is significantly more effective than endurance training only for improving EC, muscle mass and muscle strength.
There is no enough information if the combination of HIIT with high strength training (HST) could enhance the physical conditions of these patients.

Purpose
The purpose of our study was to analyze the combination of HIIT + HST and its effect on physical performance compared to different types of combined training: HIIT and MCT with low load resistance training (RT) and HIIT or MCT only.

Methods
We evaluated 140 male patients (p) with CAD documented by angiographic studies, clinically stables with medical treatment and sinus rhythm.
All of them performed a stress testing in treadmill without handrail support using a ramp protocol until maximal effort. VO2 peak (ml/kg/min) was measured indirectly through ACSM formula. We used YMCA´s method of estimating body fat with measurement of skinfolds in four sites (BF %), 30-second chair stand test (CST), 8-foot up and go test (FUGT), six-minute walk test (T6min) and one maximum repetition for quadriceps extension (1RMq) .Training intervention: p were randomly allocated to HIIT + RT (n=30), MCT + RT (n=30), HIIT (n=30), MCT (n=30) and HIIT + HST (n=20) during 3 month period of training.
HIIT: 4 x 4 (85-95% peak heart rate) and 60-70% during active breaks. (36 min)
MCT: 70-75% peak heart rate.(36 min)
RT: 40-50% 1RM for lower body with 12-15 repetitions in 2 sets
HST: ≥ 70% 1RM for lower body with low number of repetitions.
Statistical analysis: all data were analyzed using IBM SPSS V.24. Comparisons were performed by following one-way ANOVA(parametric distribution) with post-hoc Tuckey or Kruskal-Wallis(non parametric distribution). The level of statistical significance was P&lt; 0.05.

Results
Analyzing values pretraining (PRE) vs. postraining (POST), VO2 peak increased significantly by 27,52% for HIIT + HST P&lt; 0,03 vs. HIIT + RT- MCT + RT and MCT. A positive effect in HIIT + HST with FUGT P&lt; 0,001 and CST P&lt; 0,005 between group changes and favourable observations in relation to 1RMq (PRE 60,00 ± 9,07 vs. POST 73,00 ± 9,86) and %BF(PRE 26,60 ± 3,21 vs. POST 24,80 ± 3,72) compared to MCT and HIIT P &lt; 0,05. We didn´t find statistical significant differences with both modalities of combined training (low workloads) and HIIT for T6min.

Conclusions
High intensity combined training (HIIT + HST) had an additional effect related to others aerobic and resistance exercises attributed to neuromuscular adaptations, increased power and muscle strength.