Stimulus-specific functional remodeling of the left ventricle in endurance and resistance-trained men

Abstract

Left ventricular (LV) structural remodeling following athletic training has been evidenced through training-specific changes in wall thickness and geometry. Whether the LV response to changes in hemodynamic load also adapts in a training-specific manner is unknown. Using echocardiography, we examined LV responses of endurance-trained (n=15), resistance-trained (n=14), and non-athletic males (n=13) to (i) 20%, 40%, and 60% one-repetition-maximum (1RM) leg-press exercise, and (ii) intravascular Gelofusine infusion (7ml·kg-1) with passive leg-raise. While resting heart rate was lower in endurance-trained vs. controls (P=0.001), blood pressure was similar between groups. Endurance-trained individuals had lower wall thickness, but greater LV mass relative to body surface area vs. controls, with no difference between resistance-trained and controls. Leg-press evoked a similar increase in blood pressure; however, resistance-trained preserved stroke volume (SV; -3±8%) vs. controls at 60% 1RM (-15±7%, P=0.001). While the maintenance of SV was related to the change in longitudinal strain across all groups (R=0.537; P=0.007), time-to-peak strain was maintained in resistance-trained but delayed in endurance-trained individuals (1% vs. 12% delay; P=0.021). Volume infusion caused a similar increase in end-diastolic volume (EDV) and SV across groups, but leg-raise further increased EDV only in endurance-trained individuals (5±5% to 8±5%; P=0.018). Correlation analysis revealed a relationship between SV and longitudinal strain following infusion and leg-raise (R=0.334, P=0.054), however, we observed no between-group differences in longitudinal myocardial mechanics. In conclusion, resistance-trained individuals better maintained SV during pressure loading, whereas endurance-trained individuals demonstrated greater EDV reserve during volume loading. These data provide novel evidence of training-specific LV functional remodeling.

Cardiac structure and function in resistance-trained and untrained adults: A systematic review and meta-analysis

“…Of note, whilst resistance-trained athletes and non-athletes may not differ at rest, differences in systolic function (e.g. stroke volume) have been observed between these two groups during resistance exercise, therefore suggesting that favorable alterations in cardiac function in athletes occur acutely as an immediate response to the physiological stress of exercise [30].…”

Left ventricular trabeculation in Hominidae: divergence of the human cardiac phenotype

“…Echocardiographic images of healthy human adult males ( n = 18, mean age, 23.8 ± 2.8 years; body mass, 75.1 ± 8.5 kg; height, 179.8 ± 6.3 cm) and females ( n = 16, mean age 22 ± 3.3 years; body mass 62.7 ± 8.3 kg; height 168.4 ± 7.3 cm) were combined from previous studies for the human cohort 48 – 50 . Importantly, our human data align with those previously reported in large, healthy populations 51 .…”

Evidence of region‐specific right ventricular functional adaptation in endurance‐trained men in response to an acute volume infusion

“…A recent meta-analysis has confirmed such region-specific adaptations, highlighting a lower myocardial deformation at the RV base and greater deformation at the apex in endurance athletes in comparison to nonathletes (Dawkins et al, 2021). However, resting data probably do not reflect the full extent of cardiac remodelling; it is possible that regional RV function, and its response to the repetitive volume load caused by endurance exercise, might also remodel, as previously reported in the left ventricle (Dawkins et al, 2020). Moreover, the lower longitudinal deformation at the base of the RV in endurance athletes might reflect an enhanced reserve capacity to be used during exercise, as has been shown previously in the left ventricle of endurance athletes (Nottin et al, 2008).…”

“…This finding contradicts previous research, in which a greater RVSP has been observed in athletes, which is associated with larger stroke volumes (D'Andrea et al, 2011;Dawkins et al, 2021). Variability in RVSP might be attributable to a smaller magnitude of difference in stroke volume, hence pulsatile blood flow, between endurance and control groups (Dawkins et al, 2020) in comparison to others (D'Andrea et al, 2011). Pulmonary artery pressure, and therefore right ventricular systolic load, can also be elevated by increases in F I G U R E 2 Changes in regional strain values from baseline to post-infusion are reflected by squares, and changes in regional strain values from baseline to passive leg raise are reflected by circles.…”

“…Nonetheless, the same findings were observed for global RV strain (six-segment strain including free wall and septum). We appreciate that a more comprehensive assessment of the functional capacity all four chambers of the athlete's heart is required, although some of this of work is ongoing (Dawkins et al, 2020). Finally, specific studies to examine the heart of female athletes are warranted;…”