Ben T. Esch

The health benefits of interactive video game exercise.

The purpose of this study was to evaluate the effectiveness of interactive video games (combined with stationary cycling) on health-related physical fitness and exercise adherence in comparison with traditional aerobic training (stationary cycling alone). College-aged males were stratified (aerobic fitness and body mass) and then assigned randomly to experimental (n = 7) or control (n = 7) conditions. Program attendance, health-related physical fitness (including maximal aerobic power (VO2 max), body composition, muscular strength, muscular power, and flexibility), and resting blood pressure were measured before and after training (60%-75% heart rate reserve, 3 d/week for 30 min/d for 6 weeks). There was a significant difference in the attendance of the interactive video game and traditional training groups (78% +/- 18% vs. 48% +/- 29%, respectively). VO2 max was significantly increased after interactive video game (11% +/- 5%) but not traditional (3% +/- 6%) training. There was a significantly greater reduction in resting systolic blood pressure after interactive video game (132 +/- 6 vs. 123 +/- 6 mmHg) than traditional (131 +/- 7 vs. 128 +/- 8 mmHg) training. There were no significant changes in body composition after either training program. Attendance mediated the relationships between condition and changes in health outcomes (including VO2 max, vertical jump, and systolic blood pressure). The present investigation indicates that a training program that links interactive video games to cycle exercise results in greater improvements in health-related physical fitness than that seen after traditional cycle exercise training. It appears that greater attendance, and thus a higher volume of physical activity, is the mechanism for the differences in health-related physical fitness.

Left ventricular torsion and recoil: implications for exercise performance and cardiovascular disease

In recent years, advancements in echocardiography assessment techniques have allowed for the quantification of left ventricular (LV) rotation. This information has provided new insight into LV function in health and disease. In this review, we discuss the importance of assessing LV circumferential rotation for understanding cardiac function in a wide range of populations. We provide a synopsis of LV rotational mechanics in the context of the various techniques currently available to assess LV rotation. We also highlight the factors that alter LV function at rest and during exercise. Finally, we discuss the influences of age, sex, and cardiac pathology on LV rotation. Collectively, this review highlights the importance of understanding LV rotation and its measurement in both health and disease.

Cardiovascular consequences of completing a 160-km ultramarathon

PURPOSES To comprehensively investigate the cardiovascular consequences of a 160-km ultramarathon using traditional echocardiography, speckle tracking imaging, cardiac biomarkers, and heart rate variability (HRV) and to examine the relationship between the changes in these variables. METHODS We examined athletes before an ultramarathon and reassessed all finishers immediately after the race. Left ventricular (LV) systolic (ejection fraction [EF], systolic blood pressure/end-systolic volume [SBP/ESV] ratio) and diastolic (ratio of early [E] to late [A], filling E:A) measurements were assessed using traditional echocardiography, whereas myocardial peak strain and strain rate were analyzed using speckle tracking. Cardiac biomarkers measured were cardiac troponin T (cTnT) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP). HRV indices were assessed using standard frequency and time domain measures. RESULTS Twenty-five athletes successfully completed the race (25.5 +/- 3.2 h). Significant pre- to postrace changes in EF (66.8 +/- 3.8 to 61.2 +/- 4.0 %, P < 0.05) and E:A ratio (1.62 +/- 0.37 to 1.35 +/- 0.33, P < 0.05) were reported. Peak strain was significantly decreased in all planes, with the largest reduction occurring circumferentially. NT-pro-BNP concentrations increased significantly (28 +/- 17.1 vs 795 +/- 823 ng x L, P < 0.05), whereas postrace cTnT were elevated in just five athletes (20%). No significant alterations in HRV were noted postrace. Reductions in LV function were not significantly associated with changes in cardiac biomarkers and/or HRV. CONCLUSIONS Although the stress of an ultramarathon resulted in a mild reduction in LV function and biomarker release, the mechanisms behind such consequences remain unknown. It is likely that factors other than myocardial damage or strong vagal reactivation contributed to postexercise decreases in LV function after an ultramarathon.

Left ventricular torsion and untwisting during exercise in heart transplant recipients

Left ventricular (LV) rotation is the dominant deformation during relaxation and links systole with early diastolic recoil. LV torsion and untwisting rates during submaximal exercise were compared between heart transplant recipients (HTRs), young adults and healthy older individuals to better understand impaired diastolic function in HTRs. Two dimensional and colour M‐mode echocardiography with speckle‐tracking analysis were completed in eight HTRs (age: 61 ± 9 years), six recipient age‐matched (RM, age: 60 ± 11 years), and five donor age‐matched (DM, age: 35 ± 8 years) individuals (all males) at rest and during submaximal cycle exercise. LV peak torsion, peak rate of untwisting and peak intraventricular pressure gradients (IVPGs) were examined. LV torsion increased with exercise in DMs (6.5 ± 5.6 deg, P < 0.05), but not in RMs (−2.6 ± 7.0 deg) or HTRs (−0.9 ± 4.4 deg). The change from rest to exercise in the peak rate of untwisting was significantly greater for DMs (−2.1 ± 0.5 rads s−1, P < 0.05) compared to RMs (−0.7 ± 1.3 rads s−1) and HTRs (−0.2 ± 0.9 rads s−1). The amount of untwisting occurring prior to mitral valve opening substantially declined with exercise in RMs and HTRs only. The change in IVPGs was 1.3‐fold greater in DMs versus HTRs or RMs (P > 0.05). Peak LV torsion and untwisting are blunted during exercise in HTRs and RMs compared to DMs. These factors may contribute to the impaired diastolic filling found in HTRs during exercise. Similarities between HTRs and RMs during exercise suggest functional accelerated ageing of the cardiac allograft.

Metabolic Requirements of Interactive Video Game Cycling

BACKGROUND Interactive video game exercise leads to improved exercise adherence and health-related physical fitness in comparison to traditional stationary cycling. It has been postulated that interactive video game exercise has greater metabolic requirements than traditional cycling; however, this has not been tested to date. PURPOSE To examine the metabolic requirements of interactive video game exercise in comparison to traditional stationary cycling at matched incremental workloads. METHODS Fourteen participants (seven males and seven females) were examined during three separate sessions: 1) incremental cycle ergometer exercise for the assessment of maximal aerobic power and peak workload; 2) traditional cycling on a cycle ergometer using 5-min constant workloads of 25%, 50%, and 75% of maximal power output; and 3) cycling using identical constant, relative workloads while playing interactive video games. Measurements of oxygen consumption, heart rate, and rating of perceived exertion were assessed throughout. RESULTS During interactive video game exercise, steady-state heart rate (26% +/- 18% and 14% +/- 13%), energy expenditure (61% +/- 41% and 25% +/- 21%), and oxygen consumption (34% +/- 17% and 18% +/- 12%) were significantly higher at the constant submaximal workloads of 25% and 50%, respectively. There was no significant difference in rating of perceived exertion between conditions at any workload. CONCLUSIONS Interactive video game cycling results in greater metabolic requirements (despite similar perceptions of exertion) at submaximal constant workloads than traditional cycling. This form of training may be a novel and an attractive intervention in the battle against physical inactivity and associated health complications.

Upper limits of physiological cardiac adaptation in ultramarathon runners.

To the Editor: Physiologic left ventricular (LV) hypertrophy is common in endurance-trained athletes ([1][1]). Controversially, a recent report from Japan suggested that a new upper limit for physiological LV hypertrophy might be present in ultramarathon runners ([2][2]). Specifically, in 291 male

Regional muscle oxygenation differences in vastus lateralis during different modes of incremental exercise

BackgroundNear infrared spectroscopy (NIRS) is used to assess muscle oxygenation (MO) within skeletal muscle at rest and during aerobic exercise. Previous investigations have used a single probe placement to measure MO during various forms of exercise. However, regional MO differences have been shown to exist within the same muscle which suggests that different areas of the same muscle may have divergent MO. Thus, the aim of this study was to examine whether regional differences in MO exist within the same muscle during different types of incremental (rest, 25, 50, 75, 100 % of maximum) exercise (1 leg knee extension (KE), 2 leg KE, or cycling).MethodsNineteen healthy active males (Mean ± SD: Age 27 ± 4 yrs; VO2max: 55 ± 11 mL/kg/min) performed incremental exercise to fatigue using each mode of exercise. NIRS probes were placed on the distal and proximal portion of right leg vastus lateralis (VL). Results were analyzed with a 3-way mixed model ANOVA (probe × intensity × mode).ResultsDifferences in MO exist within the VL for each mode of exercise, however these differences were not consistent for each level of intensity. Comparison of MO revealed that the distal region of VL was significantly lower throughout KE exercise (1 leg KE proximal MO – distal MO = 9.9 %; 2 leg KE proximal MO – distal MO = 13 %). In contrast, the difference in MO between proximal and distal regions of VL was smaller in cycling and was not significantly different at heavy workloads (75 and 100 % of maximum).ConclusionMO is different within the same muscle and the pattern of the difference will change depending on the mode and intensity of exercise. Future investigations should limit conclusions on MO to the area under assessment as well as the type and intensity of exercise employed.

Changes in ventricular twist and untwisting with orthostatic stress: endurance athletes versus normally active individuals

Endurance-trained individuals exhibit larger reductions in left ventricular (LV) end-diastolic volume in response to lower body negative pressure (LBNP) compared with normally active individuals. However, the relationship between LV torsion and untwisting and the LV volume response to LBNP in endurance athletes is unknown. Eight endurance-trained athletes [maximal oxygen consumption (VO2max): 66.4+/-7.2 ml.kg(-1).min(-1)] and eight normally active individuals (VO2max: 41.9+/-9.0 ml.kg(-1).min(-1)) (all men) underwent two cardiac magnetic resonance imaging (MRI) assessments, the first during supine rest and the second during -30 mmHg LBNP. Right ventricular (RV) and LV volumes were assessed, myocardial tagging was applied in order to quantify LV peak torsion and peak untwisting rate, and filling rates were measured with phase-contrast MRI. In response to LBNP, endurance-trained individuals had greater reductions in RV and LV end-diastolic volume and stroke volume (P<0.05). Endurance athletes had reduced untwisting rates (20.3+/-8.7 degrees/s), while normally active individuals had increased untwisting rates (-16.2+/-32.1 degrees/s) in response to LBNP (P<0.05). Changes in peak untwisting rate were significantly correlated with change in peak torsion (R=-0.87, P<0.05), with the change in early filling rate and VO2max, but not with changes in end-diastolic or end-systolic volume (P>0.05). We conclude that increased untwisting rates in normally active subjects may mitigate the drop in early filling rate with LBNP and thus may be a compensatory mechanism for the reduction in stroke volume with volume unloading. The opposite response in athletes, who showed a decreased untwisting rate, may contribute to their larger reductions in LV end-diastolic and stroke volumes with volume unloading and their orthostatic intolerance.

Effects of High Intensity Exercise on Biventricular Function Assessed by Cardiac Magnetic Resonance Imaging in Endurance Trained and Normally Active Individuals

Although several investigations have demonstrated that prolonged aerobic exercise results in decreased left ventricular (LV) function, few have examined the impact of an acute bout of high-intensity exercise on right ventricular (RV) and LV systolic and diastolic function. Cardiac magnetic resonance imaging with tagging was used to study the impact of high-intensity interval exercise on biventricular function in 9 endurance-trained (ET; Vo(2)max 69 +/- 7 ml/kg/min) and 9 normally active (NA; Vo(2)max 44 +/- 9 ml/kg/min) men. Subjects underwent baseline cardiac magnetic resonance imaging assessments (pre) and then performed an average of 14 1-minute intervals at 97 +/- 11% (NA) and 99 +/- 6% (ET) of peak power output, separated by 2 minutes of recovery at 21 +/- 6% (NA) and 21 +/- 9% (ET) of peak power output. After exercise, 2 cardiac magnetic resonance imaging assessments (post 1 at 6.2 +/- 2.6 minutes and post 2 at 38.4 +/- 3.8 minutes) were completed. RV and LV ejection fractions, twist, basal and apical rotation rates, rate of untwisting, circumferential strain, and timings were examined. No significant change in RV and LV ejection fractions, twist, untwisting rate, or strain after exercise occurred in the NA group. In the ET group, RV ejection fraction (pre 56 +/- 4%, post 1 54 +/- 4%, post 2 54 +/- 3%) and LV ejection fraction (pre 62 +/- 4%, post 1 59 +/- 4%, post 2 58 +/- 4%) were decreased at post 1 and post 2, while untwisting rate, apical rotation rate, and circumferential strain were decreased at post 2 (all p values <0.05). In conclusion, biventricular systolic and diastolic dysfunction occurred after 14 minutes of high-intensity exercise in ET athletes, a phenomenon not observed in NA subjects.

Characterization of the Relationship between Systolic Shear Strain and Early Diastolic Shear Strain Rates: Insights into Torsional Recoil

Early diastolic left ventricular (LV) untwisting has been evaluated as a manifestation of LV recoil, reflecting the release of elastic energy stored during systole. The primary goal of this study was to characterize the relationship between systolic strain (e.g., circumferential strain and the shear strains that comprise twist) with the resulting early diastolic shear strain rates, including the rate of untwisting. A further goal was to characterize these relationships regionally from apical to basal locations. Cardiac magnetic resonance imaging tissue tagging was used to measure circumferential strain, global and regional (apex, mid, basal) twist (theta), and circumferential-longitudinal (epsilon(CL)) and circumferential-radial (epsilon(CR)) shear strains along with the corresponding untwisting rates (dtheta/dt) and diastolic shear strain rates (depsilon/dt) in 32 healthy males (33 +/- 7 yr). LV untwisting rates and shear strain rates measured during early diastole varied significantly with the measurement location from apex to base (P < 0.001) but demonstrated significant linear correlation with their corresponding preceding systolic strains (P < 0.001). Untwisting rates and diastolic shear strain rates were not significantly correlated with circumferential systolic strain or end-systolic volume (P > 0.05). Normalization of the untwisting rates to the peak twist (dtheta/dt(Norm) = -13.6 +/- 2.1 s(-1)) or shear strain rates to peak systolic shear strain (depsilon(CL)/dt(Norm) = -15.0 +/- 5.4 s(-1), and depsilon(CR)/dt(Norm) = -14.2 +/- 7.7 s(-1)) yielded a uniform measure of early diastolic function that was similar for all shear strain and twist components and for all locations from apex to base. These findings support a linear model of torsional recoil in the healthy heart, where diastolic shear strain rates (e.g., untwisting rates) are linearly related to the corresponding preceding systolic shear stain component. Furthermore, these findings suggest that torsional recoil is uncoupled from end-systolic volumes or the associated strains, such as circumferential strain.