Development of a non-damaging high-intensity intermittent running protocol

Exercise-Induced Muscle Damage after a High-Intensity Interval Exercise Session: Systematic Review

High-intensity interval training (HIIT) is considered an effective method to improve fitness and health indicators, but its high-intensity exercises and the mechanical and metabolic stress generated during the session can lead to the occurrence of exercise-induced muscle damage. Therefore, this study aimed to describe, by means of a systematic review, the effects of a single HIIT session on exercise-induced muscle damage. A total of 43 studies were found in the Medline/PubMed Science Direct/Embase/Scielo/CINAHL/LILACS databases; however, after applying the exclusion criteria, only 15 articles were considered eligible for this review. The total sample was 315 participants. Among them, 77.2% were men, 13.3% were women and 9.5 uninformed. Their age ranged from 20.1 ± 2 to 47.8 ± 7.5 years. HIIT protocols included running with ergometers (n = 6), CrossFit-specific exercises (n = 2), running without ergometers (n = 3), swimming (n = 1), the Wingate test on stationary bicycles (n = 2), and cycling (n = 1). The most applied intensity controls were %vVO2max, "all out", MV, MAV, Vmax, and HRreserve%. The most used markers to evaluate muscle damage were creatine kinase, myoglobin, and lactate dehydrogenase. The time for muscle damage assessment ranged from immediately post exercise to seven days. HIIT protocols were able to promote changes in markers of exercise-induced muscle damage, evidenced by increases in CK, Mb, LDH, AST, ALT, pain, and muscle circumference observed mainly immediately and 24 h after the HIIT session.

Cardiac Biomarkers in Sports Cardiology

Sustained physical activity induces morphological and functional changes in the cardiovascular system. While mostly physiological, they can also become a trigger for major adverse cardiovascular events, the most severe of which are sudden cardiac arrest and sudden cardiac death. Therefore, any novel method which can help more accurately estimate the cardiovascular risk should be considered for further studying and future implementation in the standard protocols. The study of biomarkers is gaining more and more ground as they have already established their utility in diagnosing ischemic cardiac disease or in evaluating cardiac dysfunction in patients with heart failure. Nowadays, they are being implemented in the screening of apparently healthy individuals for the assessment of the cardiovascular risk. The aim of this paper is to gather published data regarding the measurements of cardiac biomarkers in athletes, i.e., troponins, myoglobin, CK-MB, NT-proBNP, and D-Dimers, and their potential use in the field of sports cardiology.

Cardiopulmonary Exercise Testing and Cardiac Biomarker Measurements in Young Football Players: A Pilot Study

Constant and intense physical activity causes physiological adaptive changes in the human body, but it can also become a trigger for adverse events, such as sudden cardiac arrest or sudden cardiac death. Our main objective was to assess the use of combined cardiopulmonary exercise testing (CPET) and cardiac biomarker determinants in young professional athletes. We conducted a study which involved the full examination of 19 football players, all male, aged between 18 and 20 years old. They underwent standard clinical and paraclinical evaluation, a 12-lead electrocardiogram (ECG), and transthoracic echocardiography (TTE). Afterwards, a tailored CPET was performed and peripheral venous blood samples were taken before and 3 h after the test in order to determine five biomarker levels at rest and post-effort. The measured biomarkers were cardiac troponin I (cTnI), myoglobin (Myo), the MB isoenzyme of creatine-kinase (CK-MB), the N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and D-dimers. While cTnI and NT-proBNP levels were undetectable both at rest and post-effort in all subjects, the variations in Myo, CK-MB and D-dimers showed significant correlations with CPET parameters. This highlights the potential use of combined CPET and biomarker determinants to evaluate professional athletes, and encourages further research on larger study groups.

Effect of Low-Volume High-Intensity Interval Exercise and Continuous Exercise on Delayed-Onset Muscle Soreness in Untrained Healthy Males

Farias Junior, LF, Browne, RAV, Frazão, DT, Dantas, TCB, Silva, PHM, Freitas, RPA, Aoki, MS, and Costa, EC. Effect of low-volume high-intensity interval exercise and continuous exercise on delayed-onset muscle soreness in untrained healthy males. J Strength Cond Res 33(3): 774-782, 2019-The aim of this study was to compare the effect of a single session of a low-volume high-intensity interval exercise (HIIE) and a continuous exercise (CE) on the magnitude of delayed-onset muscle soreness (DOMS) in untrained healthy males. Fifteen participants (25.1 ± 4.4 years) completed 2 experimental sessions in a randomized order: (a) low-volume HIIE: 10 × 60 seconds at 90% of maximal velocity (MV) interspersed with 60 seconds of active recovery at 30% of MV and (b) CE: 20 minutes at 60% of MV. Pressure-pain threshold (PPT), pressure-pain tolerance (PPTol), and perceived pain intensity (PPI) were assessed in the rectus femoris, biceps femoris, and gastrocnemius before and 24 hours after exercise. There was a decrease of PPT in the rectus femoris (-0.5 kg·cm) and PPTol in the gastrocnemius (-1.4 kg·cm) and an increase of PPI in the rectus femoris (14.4 mm) and in the biceps femoris (11.7 mm) 24 hours after the low-volume HIIE session (p ≤ 0.05). There was a decrease of PPT (rectus femoris: -0.8 kg·cm; biceps femoris: -0.5 kg·cm; gastrocnemius: -0.9 kg·cm) and PPTol (rectus femoris: -1.9 kg·cm; biceps femoris: -2.7 kg·cm; gastrocnemius: -1.6 kg·cm) and an increase of PPI (rectus femoris: 8.1 mm; biceps femoris: 10.3 mm; gastrocnemius: 17.5 mm) in all muscles 24 hours after the CE session (p ≤ 0.05). No difference was observed between HIIE and CE sessions in any DOMS-related parameter (p > 0.05). In conclusion, a single session of low-volume HIIE and CE elicited a similar mild DOMS 24 hours after exercise in untrained healthy males.

Passive and post-exercise cold-water immersion augments PGC-1α and VEGF expression in human skeletal muscle

Purpose

We tested the hypothesis that both post-exercise and passive cold water immersion (CWI) increases PGC-1α and VEGF mRNA expression in human skeletal muscle.

Method

Study 1 Nine males completed an intermittent running protocol (8 × 3-min bouts at 90 % \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}{\text{O}}_{2} \hbox{max}$$\end{document}V˙O2max, interspersed with 3-min active recovery (1.5-min at 25 % and 1.5-min at 50 % \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}{\text{O}}_{2} \hbox{max}$$\end{document}V˙O2max) before undergoing CWI (10 min at 8 °C) or seated rest (CONT) in a counterbalanced, randomised manner. Study 2 Ten males underwent an identical CWI protocol under passive conditions.

Results

Study 1 PGC-1α mRNA increased in CONT (~3.4-fold; P < 0.001) and CWI (~5.9-fold; P < 0.001) at 3 h post-exercise with a greater increase observed in CWI (P < 0.001). VEGFtotal mRNA increased after CWI only (~2.4-fold) compared with CONT (~1.1-fold) at 3 h post-exercise (P < 0.01). Study 2 Following CWI, PGC-1α mRNA expression was significantly increased ~1.3-fold (P = 0.001) and 1.4-fold (P = 0.0004) at 3 and 6 h, respectively. Similarly, VEGF165 mRNA was significantly increased in CWI ~1.9-fold (P = 0.03) and 2.2-fold (P = 0.009) at 3 and 6 h post-immersion.

Conclusions

Data confirm post-exercise CWI augments the acute exercise-induced expression of PGC-1α mRNA in human skeletal muscle compared to exercise per se. Additionally CWI per se mediates the activation of PGC-1α and VEGF mRNA expression in human skeletal muscle. Cold water may therefore enhance the adaptive response to acute exercise.