Cardiac Structural and Functional Changes in Competitive Amateur Cyclists

Pulmonary Aspects of Exercise and Sports

Although the lungs are a critical component of exercise performance, their response to exercise and other environmental stresses is often overlooked when evaluating pulmonary performance during high workloads. Exercise can produce capillary leakage, particularly when left atrial pressure increases related to left ventricular (LV) systolic or diastolic failure. Diastolic LV dysfunction that results in elevated left atrial pressure during exercise is particularly likely to result in pulmonary edema and capillary hemorrhage. Data from race horses, endurance athletes, and triathletes support the concept that the lungs can react to exercise and immersion stress with pulmonary edema and pulmonary hemorrhage. Immersion in water by swimmers and divers can also increase stress on pulmonary capillaries and result in pulmonary edema. Swimming-induced pulmonary edema and immersion pulmonary edema in scuba divers are well-documented events caused by the fluid shifts that occur with immersion, elevated pulmonary venous pressure during extreme exercise, and negative alveolar pressure due to inhalation resistance. Prevention strategies include avoiding extreme exercise, avoiding over hydration, and assuring that inspiratory resistance is minimized.

Endurance and Strength Athlete's Heart: Analysis of Myocardial Deformation by Speckle Tracking Echocardiography

Background

Intensive training induces two morphological myocardial typologies of athlete's heart. Endurance training (ET) induces eccentric remodeling, bradycardia and better diastolic filling. Strength training (ST) determines concentric chamber remodelling maintaining a normal heart rate (HR). Aim of the study was to compare ET and ST athletes' heart using speckle tracking echocardiography (STE).

Methods

33 professional ET, 36 ST athletes, and 17 healthy controls (CT) were enrolled. All subjects underwent standard transthoracic echocardiography at rest and STE.

Results

In ET group, HR was lower than ST group and CT group (p < 0.001; p < 0.01). ET group had higher E/A ratio than ST group and CT group (p < 0.01; p < 0.001). The left ventricular apical circumferential strain in ET group was lower than ST group and CT group (-21.6 ± 4.1% vs. -26.8 ± 7.7%, p < 0.05; vs. -27.8 ± 5.6%, p < 0.01). ET group had lower left ventricular twist (LVT) and untwisting (UTW) than ST group (6.2 ± 0.1° vs. 12.0 ± 0.1°, p < 0.01; -67.3 ± 22.9°/s vs. -122.5 ± 52.8°/s, p < 0.01) and CT group (10.0 ± 0.1°, p < 0.01; -103.3 ± 29.3°/s, p < 0.01). The univariate analysis showed significant correlation between E/A ratio and HR (r = -0.54; p < 0.001), LVT (r = -0.45; p < 0.01), UTW (r = 0.24; p < 0.05). At the multivariate analysis only HR was confirmed as independent predictor of diastolic function in all groups (Beta -0.52; p < 0.001).

Conclusion

In ET there was a better global systolic and diastolic functional reserve at rest observed with strain analysis and it maybe depended on autonomic modulation.

Rowing increases stroke volume and cardiac output to a greater extent than cycling

Exercise stimulates increases in heart rate (HR), stroke volume (SV) and cardiac output (CO). These adaptive mechanisms are strongly dependent on the type of exercise. Both rowing and cycling are widely used for physical training worldwide; however, evidence regarding the differences in major hemodynamic parameters during rowing and cycling remains insufficient. Ten healthy male volunteers were randomly assigned to perform either a rowing or cycling exercise. After 20 min rest, the group who had rowed first performed the cycling exercise and vice versa. Exercise was performed at a power-to-weight ratio of 2 W/kg for 2 min. HR, SV, CO and blood pressure (BP) were measured noninvasively using pulse-wave analysis at baseline and immediately after each exercise. HR, SV and CO were significantly higher after exercise than at rest. Whereas HR was comparable between rowing and cycling, SV and CO were significantly higher after rowing than after cycling. BP was comparable among all three measurements. Rowing increased SV and CO to a greater extent than cycling, whereas HR and BP were not influenced by the type of exercise. Our data suggest that rowing leads to more extensive stimulation of cardiac contractility and/or decreases in peripheral vascular resistance compared with cycling.