Effect of intensive resistance training on isotonic exercise Doppler indexes of left ventricular systolic function

The toll of the gridiron: damage-associated molecular patterns and hypertension in American football

American football has unequivocally been linked to elevations in blood pressure and hypertension, especially in linemen. However, the mechanisms of this increase cannot be attributed solely to increased body weight and associated cardiometabolic risk factors (e.g.,dyslipidemia or hyperglycemia). Therefore, understanding the etiology of football-associated hypertension is essential for improving the quality of life in this mostly young population, as well as for lowering the potential for chronic disease in the future. We propose that inflammatogenic damage-associated molecular patterns (DAMPs) released into the circulation from football-induced musculoskeletal trauma activate pattern-recognition receptors of the innate immune system-specifically, high mobility group box 1 protein (HMGB1) and mitochondrial (mt)DNA which activate Toll-like receptor (TLR)4 and -9, respectively. Previously, we observed that circulating levels of these 2 DAMPs are increased in hypertension, and activation of TLR4 and -9 causes endothelial dysfunction and hypertension. Therefore, our novel hypothesis is that musculoskeletal injury from repeated hits in football players, particularly in linemen, leads to elevated circulating HMGB1 and mtDNA to activate TLRs on endothelial cells leading to impaired endothelium-dependent vasodilation, increased vascular tone, and hypertension.

Left Atrium Size in Elite Athletes

OBJECTIVES

The goal of this study was to perform a meta-analysis of the published literature to investigate the relationship of high levels of exercise training to left atrial (LA) size.

BACKGROUND

The "athlete's heart" is a series of cardiac adaptations to systematic exercise training and may include LA enlargement.

METHODS

We conducted a systematic review of English-language studies in MEDLINE and Scopus from inception through April 29, 2014, that reported LA size in elite athletes.

RESULTS

A total of 54 studies comprising 7,189 elite athletes and 1,375 controls were included. Forty-eight of the 54 studies reported absolute LA diameter in 7,018 athletes and 1,044 controls. Nine of the 54 studies (including 992 athletes and 426 controls) presented LA volume corrected for body surface area. The adjusted weighted mean LA diameter was 4.1 mm greater in athletes overall compared with sedentary controls (p < 0.0001), and LA volume index was 7.0 ml/m(2) greater in athletes than controls (p < 0.01). Compared with controls, LA diameter was 4.6 mm greater in endurance-trained athletes (p < 0.0001), 2.9 mm greater in strength-trained athletes (p < 0.03), 3.5 mm greater in combined strength- and endurance-trained athletes (p < 0.0001), and 4.2 mm greater in athletes with unspecified training (p < 0.02).

CONCLUSIONS

To our knowledge, this is the largest compilation of studies documenting that elite athletes have larger LA dimensions compared with controls when evaluated by either LA diameter or LA volume corrected for body surface area. The largest average LA diameters were reported in endurance athletes. Physicians evaluating athletes should be aware that the LA is increased in both strength- and endurance-trained elite athletes.

Cardiovascular adaptations to 4 and 12 months of football or strength training in 65- to 75-year-old untrained men

The study examined the effects of 1 year of football or strength training on cardiovascular function in 65- to 75-year-old men. Twenty-six untrained men (age: 68.2 ± 3.2 years) were randomized to football training (FTG; n = 9), strength training (STG; n = 9), or control (CG; n = 8). In FTG, left ventricular (LV) internal diastolic diameter, end-diastolic volume, and mass index were 8%, 21%, and 18% higher (P < 0.01), respectively, after 12 months, with no changes in STG and CG. After 12 months, LV ejection fraction was increased (P < 0.05) by 8% and 5% in FTG and STG, respectively, and systolic longitudinal two-dimensional strain by 8% and 6%, whereas right ventricular systolic function improved (P < 0.05) by 22% in FTG, but not in STG and CG. In FTG, LV diastolic mitral inflow (E/A) ratio and peak early diastolic velocity (E') improved (P < 0.05) by 25% and 12%, respectively, after 12 months, with no changes in STG and CG. In FTG, maximum oxygen uptake was 16% and 18% higher (P < 0.001) after 4 and 12 months, respectively, and resting heart rate was 6 and 8 beats per minute lower (P < 0.001), respectively, with no changes in STG and CG. In conclusion, football training elicited superior cardiovascular effects compared with strength training in elderly untrained men.

Exercise-induced cardiac remodeling

Early investigations in the late 1890s and early 1900s documented cardiac enlargement in athletes with above-normal exercise capacity and no evidence of cardiovascular disease. Such findings have been reported for more than a century and continue to intrigue scientists and clinicians. It is well recognized that repetitive participation in vigorous physical exercise results in significant changes in myocardial structure and function. This process, termed exercise-induced cardiac remodeling (EICR), is characterized by structural cardiac changes including left ventricular hypertrophy with sport-specific geometry (eccentric vs concentric). Associated alterations in both systolic and diastolic functions are emerging as recognized components of EICR. The increasing popularity of recreational exercise and competitive athletics has led to a growing number of individuals exhibiting these findings in routine clinical practice. This review will provide an overview of EICR in athletes.

Anabolic androgenic steroid use is associated with ventricular dysfunction on cardiac MRI in strength trained athletes

BACKGROUND

Uncertainty remains about possible cardiac adaptation to resistance training. Androgenic anabolic steroids (AAS) use plays a potential role and may have adverse cardiovascular effects.

OBJECTIVE

To elucidate the effect of resistance training and of AAS-use on cardiac dimensions and function.

PARTICIPANTS

Cardiac magnetic resonance (CMR) were performed in 156 male subjects aged 18-40 years: 52 non-athletes (maximum of 3 exercise hours/week), 52 strength-endurance (high dynamic-high static, HD-HS) athletes and 52 strength (low dynamic-high static, LD-HS) trained athletes (athletes ≥ 6 exercise hours/week). 28 LD-HS athletes denied and 24 admitted to AAS use for an average duration of 5 years (range 3 months-20 years).

RESULTS

No significant differences were found between non-athletes and non-AAS-using LD-HS athletes. AAS-using LD-HS athletes had significantly larger LV and RV volumes and LV wall mass than non-AAS-using LD-HS athletes, but lower than HD-HS athletes. In comparison to all other groups AAS-using LD-HS athletes showed lower ejection fractions of both ventricles (LV/RV EF 51/48% versus 55-57/51-52%) and lower E/A ratios (LV/RV 1.5/1.2 versus 1.9-2.0/1.4-1.5) as an indirect measure of diastolic function. Linear regression models demonstrated a significant effect of AAS-use on LV EDV, LV EDM, systolic function and mitral valve E/A ratio (all ANOVA-tests p<0.05).

CONCLUSIONS

Strength athletes who use AAS show significantly different cardiac dimensions and biventricular systolic dysfunction and impaired ventricular inflow as compared to non-athletes and non-AAS-using strength athletes. Increased ventricular volume and mass did not exceed that of strength-endurance athletes. These findings may help raise awareness of the consequences of AAS use.

A systematic review of resting left ventricular systolic and diastolic function and adaptation in elite weightlifters

BACKGROUND

This review aims to establish what effect weightlifting has on the systolic and diastolic function of the left ventricular (LV).

SOURCES OF DATA

PubMed; ISI Web of Knowledge; Cochrane Library and Ovid Medline were searched in February 2012 to find literature on the effect of weightlifting on the LV cardiac function.

AREAS OF AGREEMENT

Stroke volume, posterior wall thickness and ventricular filling time and rate were seen to increase. A decrease in the resting heart rate was seen.

AREAS OF CONTROVERSY

Blood pressure and LV morphological changes were equivocal.

GROWING POINTS

Weightlifting causes recognizable functional change to the LV, some of these changes may confer benefits such as improvements in the systolic function.

AREAS TIMELY FOR DEVELOPING RESEARCH

Discrepancies exist with regard to regional LV morphological change, as the evidence suggests the LV does not adapt in a homogenous manner. Attempts should be made to separate performance-enhancing drug users from those who compete drug free.

Left ventricular diastolic function in trained male weight lifters at rest and during isometric exercise

Individuals involved in intense resistance training present with increased absolute left ventricular (LV) wall thickness and mass and show good systolic responses to isometric exercise. There is no consensus regarding diastolic features and no available information regarding diastolic function in athletes during isometric exertion itself. Therefore, the main aim of this study was to assess diastolic LV function at baseline and during exercise in athletes. The population consisted of 96 men (mean age 29 +/- 7 years): 48 weight lifters who trained for 15 to 20 hours/week and 48 sedentary men. All weight lifters had been active for >6 years, including the 6 months before the study. Ultrasound was performed using a commercially available Doppler echocardiographic system. Isometric exercise was performed in the supine position using a standard 2-hand bar dynamometer. The man end-diastolic volumes at rest were 97 +/- 6 ml in sedentary subjects and 101 +/- 5 ml in weight lifters, increasing to 100 +/- 6 and 118 +/- 11 ml during exercise (p = 0.06 and p <0.01, respectively). End-systolic volumes at rest were similar in the 2 groups, showing significantly greater reductions during exercise in the weight lifters. The mean absolute LV mass was 167 +/- 30 g in sedentary subjects and 202 +/- 32 g in weight lifters (p <0.0001). The mean stroke volume increased from 65 +/- 7 to 86 +/- 7 ml in sedentary subjects and from 70 +/- 6 to 107 +/- 11 ml in weight lifters (intergroup significance p = 0.05 and p <0.01, respectively). A similar pattern of response was documented for the ejection fraction (i.e., significantly greater increases during exercise in weight lifters). Regarding diastolic indexes, in the weight lifters, the mean peak early velocity at rest was 68 +/- 7 cm/s, the mean acceleration rate was 1,242 +/- 176 cm/s/s, and the mean deceleration rate was 414 +/- 44 cm/s/s. All these values were significantly higher than in sedentary subjects, with further increases during exercise (p <0.0001). In weight lifters, the mean peak atrial velocity at rest was 37 +/- 6 cm/s, the mean acceleration time was 55 +/- 4 ms, the mean isovolumic relaxation time was 63 +/- 3 ms, and the mean deceleration time was 164 +/- 4 ms; these values were lower than in sedentary subjects (p <0.0001 for all). In conclusion, intense resistance training leads to enhanced LV diastolic function at rest and during isometric exercise despite the markedly increased LV mass.