Ole J Kemi

University of Glasgow, Glasgow, SCT, United Kingdom

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Publications (74)266.1 Total impact

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    ABSTRACT: We describe a novel two-photon (2P) laser scanning microscopy (2PLSM) protocol that provides ratiometric transmural measurements of membrane voltage (Vm ) via Di-4-ANEPPS in intact mouse, rat and rabbit hearts with subcellular resolution. The same cells were then imaged with Fura-2/AM for intracellular Ca(2+) recordings. Action potentials (APs) were accurately characterized by 2PLSM vs. microelectrodes, albeit fast events (<1 ms) were sub-optimally acquired by 2PLSM due to limited sampling frequencies (2.6 kHz). The slower Ca(2+) transient (CaT) time course (>1ms) could be accurately described by 2PLSM. In conclusion, Vm - and Ca(2+) -sensitive dyes can be 2P excited within the cardiac muscle wall to provide AP and Ca(2+) signals to ∼400 µm. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).
    Journal of Biophotonics 10/2013; · 3.86 Impact Factor
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    ABSTRACT: BACKGROUND: -Electrical excitability in the ventricular wall is influenced by cellular electrophysiology and passive electrical properties of the myocardium. Action potential (AP) rise time, an indicator of myocardial excitability, is influenced by conduction pattern and distance from the epicardial surface. This study examined AP rise times and conduction velocity (CV) as the depolarising wavefront approaches the epicardial surface. METHODS AND RESULTS: -Two-photon excitation of di-4-ANEPPS was used to measure electrical activity at discrete epicardial layers of isolated Langendorff-perfused rabbit hearts to a depth of 500μm. Endo-to-epicardial wavefronts were studied during right atrial (RA) or ventricular endocardial pacing. Similar measurements were made with epi-to-endocardial, transverse, and longitudinal pacing protocols. Results were compared with data from a bi-domain model of 3-dimensional electrical propagation within ventricular myocardium. During RA and endocardial pacing, AP rise time (10-90% of upstroke) decreased by ~50% between 500μm and 50μm from the epicardial surface, while CV increased and AP duration was only slightly shorter (~4%). These differences were not observed with other conduction patterns. The depth-dependent changes in rise time were larger at higher pacing rates. Modelling data qualitatively reproduced the behaviour seen experimentally and demonstrated a parallel reduction in peak INa and electrotonic load as the wavefront approaches the epicardial surface. CONCLUSIONS: -Decreased electrotonic load at the epicardial surface results in more rapid AP upstrokes and higher CVs compared to the bulk myocardium. Combined effects of tissue depth and pacing rate on AP rise time reduce conduction safety and myocardial excitability within the ventricular wall.
    Circulation Arrhythmia and Electrophysiology 06/2013; · 5.95 Impact Factor
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    ABSTRACT: The tolerable duration of continuous high-intensity exercise is determined by the hyperbolic Speed-tolerable duration (S-tLIM) relationship. However, application of the S-tLIM relationship to normalize the intensity of High-Intensity Interval Training (HIIT) has yet to be considered, with this the aim of present study. Subjects completed a ramp-incremental test, and series of 4 constant-speed tests to determine the S-tLIM relationship. A sub-group of subjects (n = 8) then repeated 4 min bouts of exercise at the speeds predicted to induce intolerance at 4 min (WR4), 6 min (WR6) and 8 min (WR8), interspersed with bouts of 4 min recovery, to the point of exercise intolerance (fixed WR HIIT) on different days, with the aim of establishing the work rate that could be sustained for 960 s (i.e. 4×4 min). A sub-group of subjects (n = 6) also completed 4 bouts of exercise interspersed with 4 min recovery, with each bout continued to the point of exercise intolerance (maximal HIIT) to determine the appropriate protocol for maximizing the amount of high-intensity work that can be completed during 4×4 min HIIT. For fixed WR HIIT tLIM of HIIT sessions was 399±81 s for WR4, 892±181 s for WR6 and 1517±346 s for WR8, with total exercise durations all significantly different from each other (P<0.050). For maximal HIIT, there was no difference in tLIM of each of the 4 bouts (Bout 1: 229±27 s; Bout 2: 262±37 s; Bout 3: 235±49 s; Bout 4: 235±53 s; P>0.050). However, there was significantly less high-intensity work completed during bouts 2 (153.5±40. 9 m), 3 (136.9±38.9 m), and 4 (136.7±39.3 m), compared with bout 1 (264.9±58.7 m; P>0.050). These data establish that WR6 provides the appropriate work rate to normalize the intensity of HIIT between subjects. Maximal HIIT provides a protocol which allows the relative contribution of the work rate profile to physiological adaptations to be considered during alternative intensity-matched HIIT protocols.
    PLoS ONE 01/2013; 8(11):e76420. · 3.53 Impact Factor
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    ABSTRACT: ABSTRACT Objectives: To investigate the mechanisms of losartan- and exercise training-induced improvements on endothelial dysfunction in heart failure. Design: Sprague-Dawley rats subjected to left coronary artery ligation inducing myocardial infarction and heart failure were randomized to losartan treatment, high-intensity exercise training, or both. Results: Losartan, but not exercise training, reduced the heart failure-associated elevation in left ventricular end-diastolic pressure (26±2 mmHg vs. 19±1 mmHg after losartan). In contrast, both exercise training and losartan improved exercise capacity, by 40% and 20%, respectively; no additional effects were observed when exercise training and losartan were combined. Aortic segments were mounted on a force transducer to determine vasorelaxation. Heart failure impaired endothelium-dependent vasorelaxation, observed as a 1.9-fold reduced response to acetylcholine (EC(50)). Exercise and losartan improved acetylcholine-mediated vasorelaxation to the same extent, but by different mechanisms. Exercise training upregulated the nitric oxide pathway, whereas losartan upregulated a non-nitric oxide or -prostacyclin pathway; possibly involving the endothelium-dependent hyperpolarizing factor. Conclusions: Both losartan and exercise training reversed endothelial dysfunction in heart failure; exercise training via nitric oxide-dependent vasorelaxation, and losartan via an unknown mechanism that may involve endothelium-dependent hyperpolarizing factor. Thus, the combined treatment activated an additional nitric oxide-independent mechanism that contributed to reduce endothelial dysfunction.
    Scandinavian cardiovascular journal: SCJ 12/2012; · 1.07 Impact Factor
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    ABSTRACT: Low aerobic exercise capacity is a powerful predictor of premature morbidity and mortality for healthy adults as well as those with cardiovascular disease. For aged populations, poor performance on treadmill or extended walking tests indicates closer proximity to future health declines. Together, these findings suggest a fundamental connection between aerobic capacity and longevity. Through artificial selective breeding, we developed an animal model system to prospectively test the association between aerobic exercise capacity and survivability (aerobic hypothesis). Laboratory rats of widely diverse genetic backgrounds (N:NIH stock) were selectively bred for low or high intrinsic (inborn) treadmill running capacity. Cohorts of male and female rats from generations 14, 15, and 17 of selection were followed for survivability and assessed for age-related declines in cardiovascular fitness including maximal oxygen uptake (VO(2max)), myocardial function, endurance performance, and change in body mass. Median lifespan for low exercise capacity rats was 28% to 45% shorter than high capacity rats (hazard ratio, 0.06; P<0.001). VO(2max), measured across adulthood was a reliable predictor of lifespan (P<0.001). During progression from adult to old age, left ventricular myocardial and cardiomyocyte morphology, contractility, and intracellular Ca(2+) handling in both systole and diastole, as well as mean blood pressure, were more compromised in rats bred for low aerobic capacity. Physical activity levels, energy expenditure (Vo(2)), and lean body mass were all better sustained with age in rats bred for high aerobic capacity. These data obtained from a contrasting heterogeneous model system provide strong evidence that genetic segregation for aerobic exercise capacity can be linked with longevity and are useful for deeper mechanistic exploration of aging.
    Circulation Research 09/2011; 109(10):1162-72. · 11.09 Impact Factor
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    ABSTRACT: The response of transverse (T)-tubules to exercise training in health and disease remains unclear. Therefore, we studied the effect of exercise training on the density and spacing of left ventricle cardiomyocyte T-tubules in normal and remodeled hearts that associate with detubulation, by confocal laser scanning microscopy. First, exercise training in normal rats increased cardiomyocyte volume by 16% (P < 0.01), with preserved T-tubule density. Thus, the T-tubules adapted to the physiologic hypertrophy. Next, we studied T-tubules in a rat model of metabolic syndrome with pressure overload-induced concentric left ventricle hypertrophy, evidenced by 15% (P < 0.01) increased cardiomyocyte size. These rats had only 85% (P < 0.01) of the T-tubule density of control rats. Exercise training further increased cardiomyocyte volume by 8% (P < 0.01); half to that in control rats, but the T-tubule density remained unchanged. Finally, post-myocardial infarction heart failure induced severe cardiac pathology, with a 70% (P < 0.01) increased cardiomyocyte volume that included both eccentric and concentric hypertrophy and 55% (P < 0.01) reduced T-tubule density. Exercise training reversed 50% (P < 0.01) of the pathologic hypertrophy, whereas the T-tubule density increased by 40% (P < 0.05) compared to sedentary heart failure, but remained at 60% of normal hearts (P < 0.01). Physiologic hypertrophy associated with conserved T-tubule spacing (~1.8-1.9 µm), whereas in pathologic hypertrophy, T-tubules appeared disorganized without regular spacing. In conclusion, cardiomyocytes maintain the relative T-tubule density during physiologic hypertrophy and after mild concentric pathologic hypertrophy, whereas after severe pathologic remodeling with a substantial loss of T-tubules; exercise training reverses the remodeling and partly corrects the T-tubule density.
    Journal of Cellular Physiology 09/2011; 226(9):2235-43. · 3.87 Impact Factor
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    ABSTRACT: Activation of the multifunctional Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) plays a critical role modulating cardiac function in both health and disease. Here, we determined the effect of chronic CaMKII inhibition during an exercise training program in healthy mice. CaMKII was inhibited by KN-93 injections. Mice were randomized to the following groups: sham sedentary, sham exercise, KN-93 sedentary, and KN-93 exercise. Cardiorespiratory function was evaluated by ergospirometry during treadmill running, echocardiography, and cardiomyocyte fractional shortening and calcium handling. The results revealed that KN-93 alone had no effect on exercise capacity or fractional shortening. In sham animals, exercise training increased maximal oxygen uptake by 8% (p < 0.05) compared to a 22% (p < 0.05) increase after exercise in KN-93 treated mice (group difference p < 0.01). In contrast, in vivo fractional shortening evaluated by echocardiography improved after exercise in sham animals only: from 25 to 32% (p < 0.02). In inactive mice, KN-93 reduced rates of diastolic cardiomyocyte re-lengthening (by 25%, p < 0.05) as well as Ca(2+) transient decay (by 16%, p < 0.05), whereas no such effect was observed after exercise training. KN-93 blunted exercise training response on cardiomyocyte fractional shortening (63% sham vs. 18% KN-93; p < 0.01 and p < 0.05, respectively). These effects could not be solely explained by the Ca(2+) transient amplitude, as KN-93 reduced it by 20% (p < 0.05) and response to exercise training was equal (64% sham and 47% KN-93; both p < 0.01). We concluded that chronic CaMKII inhibition increased time to 50% re-lengthening which were recovered by exercise training, but paradoxically led to a greater increase in maximal oxygen uptake compared to sham mice. Thus, the effect of chronic CaMKII inhibition is multifaceted and of a complex nature.
    Arbeitsphysiologie 05/2011; 112(2):579-88. · 2.30 Impact Factor
  • J Helgerud, G Rodas, O J Kemi, J Hoff
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    ABSTRACT: We aimed to improve the physical capacity of a top-level elite football team during its pre-season by implementing a maximal strength and high-intensity endurance training program. 21 first league elite football players (20-31 yrs, height 171-194 cm, mass 58.8-88.1 kg) having recently participated in the UEFA Champions' League, took part in the study. Aerobic interval-training at 90-95% of maximal heart rate and half-squats strength training with maximum loads in 4 repetitions × 4 sets were performed concurrently twice a week for 8 weeks. The players were not familiar with maximal strength training as part of their regular program. Maximal oxygen uptake (VO(2max)) increased 8.6% (1.7-16.6) (p<0.001), from 60.5 (51.7-67.1) to 65.7 (58.0-74.5) mL · kg (-1) · min (-1) whereas half-squat one repetition maximum increased 51.7% (13.3-135.3) (p<0.001), from 116 (85-150) to 176 (160-210) kg. The 10-m sprint time also improved by 0.06 s (0.02-0.16) (p<0.001); while counter movement jump improved 3.0 cm (0.1-6.2) (p<0.001), following the training program. The concurrent strength and endurance training program together with regular football training resulted in considerable improvement of the players' physical capacity and so may be successfully introduced to elite football players.
    International Journal of Sports Medicine 05/2011; 32(9):677-82. · 2.27 Impact Factor
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    ABSTRACT: Impaired cardiac control of intracellular diastolic Ca(2+) gives rise to arrhythmias. Whereas exercise training corrects abnormal cyclic Ca(2+) handling in heart failure, the effect on diastolic Ca(2+) remains unstudied. Here, we studied the effect of exercise training on the generation and propagation of spontaneous diastolic Ca(2+) waves in failing cardiomyocytes. Post-myocardial infarction heart failure was induced in Sprague-Dawley rats by coronary artery ligation. Echocardiography confirmed left ventricular infarctions of 40 ± 5%, whereas heart failure was indicated by increased left ventricular end-diastolic pressures, decreased contraction-relaxation rates, and pathological hypertrophy. Spontaneous Ca(2+) waves were imaged by laser linescanning confocal microscopy (488 nm excitation/505-530 nm emission) in 2 µM Fluo-3-loaded cardiomyocytes at 37°C and extracellular Ca(2+) of 1.2 and 5.0 mM. These studies showed that spontaneous Ca(2+) wave frequency was higher at 5.0 mM than 1.2 mM extracellular Ca(2+) in all rats, but failing cardiomyocytes generated 50% (P < 0.01) more waves compared to sham-operated controls at Ca(2+) 1.2 and 5.0 mM. Exercise training reduced the frequency of spontaneous waves at both 1.2 and 5.0 mM Ca(2+) (P < 0.05), although complete normalization was not achieved. Exercise training also increased the aborted/completed ratio of waves at 1.2 mM Ca(2+) (P < 0.01), but not 5.0 mM. Finally, we repeated these studies after inhibiting the nitric oxide synthase with L-NAME. No differential effects were found; thus, mediation did not involve the nitric oxide synthase. In conclusion, exercise training improved the cardiomyocyte control of diastolic Ca(2+) by reducing the Ca(2+) wave frequency and by improving the ability to abort spontaneous Ca(2+) waves after their generation, but before cell-wide propagation.
    Journal of Cellular Physiology 04/2011; 227(1):20-6. · 3.87 Impact Factor
  • Biophysical Journal 02/2011; 100(3). · 3.83 Impact Factor
  • Biophysical Journal 01/2011; 100. · 3.83 Impact Factor
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    ABSTRACT: Maximal strength training with a focus on maximal mobilization of force in the concentric phase improves endurance performance that employs a large muscle mass. However, this has not been studied during work with a small muscle mass, which does not challenge convective oxygen supply. We therefore randomized 23 adult females with no arm-training history to either one-arm maximal strength training or a control group. The training group performed five sets of five repetitions of dynamic arm curls against a near-maximal load, 3 days a week for 8 weeks. This training increased maximal strength by 75% and improved rate of force development during both strength and endurance exercise, suggesting that each arm curl became more efficient. This coincided with a 17-18% reduction in oxygen cost at standardized submaximal workloads (work economy), and a 21% higher peak oxygen uptake and 30% higher peak load during maximal arm endurance exercise. Blood flow assessed by Doppler ultrasound in the axillary artery supplying the working biceps brachii and brachialis muscles could not explain the training-induced adaptations. These data suggest that maximal strength training improved work economy and endurance performance in the skeletal muscle, and that these effects are independent of convective oxygen supply.
    Journal of Sports Sciences 01/2011; 29(2):161-70. · 2.08 Impact Factor
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    ABSTRACT: High-intensity exercise training contributes to the production and accumulation of blood lactate, which is cleared by active recovery. However, there is no commonly agreed intensity or mode for clearing accumulated blood lactate. We studied clearance of accumulated blood lactate during recovery at various exercise intensities at or below the lactate threshold after high-intensity interval runs that prompted lactate accumulation. Ten males repeated 5-min running bouts at 90% of maximal oxygen uptake (VO(2max)), which increased blood lactate concentration from 1.0 +/- 0.1 to 3.9 +/- 0.3 mmol l(-1). This was followed by recovery exercises ranging from 0 to 100% of lactate threshold. Repeated blood lactate measurements showed faster clearance of lactate during active versus passive recovery, and that the decrease in lactate was more rapid during higher (60-100% of lactate threshold) than lower (0-40% of lactate threshold) (P < 0.05) intensities. The more detailed curve and rate analyses showed that active recovery at 80-100% of lactate threshold had shorter time constants for 67% lactate clearance and higher peak clearance rates than 40% of lactate threshold or passive recovery (P < 0.05). Finally, examination of self-regulated intensities showed enhanced lactate clearance during higher versus lower intensities, further validating the intensity dependence of clearance of accumulated blood lactate. Therefore, active recovery after strenuous exercise clears accumulated blood lactate faster than passive recovery in an intensity-dependent manner. Maximum clearance occurred at active recovery close to the lactate threshold.
    Journal of Sports Sciences 07/2010; 28(9):975-82. · 2.08 Impact Factor
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    O J Kemi, U Wisløff
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    ABSTRACT: One of the main outcomes of aerobic endurance exercise training is the improved maximal oxygen uptake, and this is pivotal to the improved work capacity that follows the exercise training. Improved maximal oxygen uptake in turn is at least partly achieved because exercise training increases the ability of the myocardium to produce a greater cardiac output. In healthy subjects, this has been demonstrated repeatedly over many decades. It has recently emerged that this scenario may also be true under conditions of an initial myocardial dysfunction. For instance, myocardial improvements may still be observed after exercise training in post-myocardial infarction heart failure. In both health and disease, it is the changes that occur in the individual cardiomyocytes with respect to their ability to contract that by and large drive the exercise training-induced adaptation to the heart. Here, we review the evidence and the mechanisms by which exercise training induces beneficial changes in the mammalian myocardium, as obtained by means of experimental and clinical studies, and argue that these changes ultimately alter the function of the whole heart and contribute to the changes in whole-body function.
    Acta Physiologica 03/2010; 199(4):425-39. · 4.25 Impact Factor
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    Y Wang, U Wisloff, O J Kemi
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    ABSTRACT: Exercise training-induced cardiac hypertrophy occurs following a program of aerobic endurance exercise training and it is considered as a physiologically beneficial adaptation. To investigate the underlying biology of physiological hypertrophy, we rely on robust experimental models of exercise training in laboratory animals that mimic the training response in humans. A number of experimental strategies have been established, such as treadmill and voluntary wheel running and swim training models that all associate with cardiac growth. These approaches have been applied to numerous animal models with various backgrounds. However, important differences exist between these experimental approaches, which may affect the interpretation of the results. Here, we review the various approaches that have been used to experimentally study exercise training-induced cardiac hypertrophy; including the advantages and disadvantages of the various models.
    Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(5):633-44. · 1.49 Impact Factor
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    ABSTRACT: This chapter compares the imaging capabilities of a range of systems including multiphoton microscopy in regard to measurements of intracellular Ca(2+) within living cells. In particular, the excitation spectra of popular fluorescent Ca(2+) indicators are shown during 1P and 2P excitation. The strengths and limitations of the current indicators are discussed along with error analysis which highlights the value of matching the Ca(2+) affinity of the dye to a particular aspect of Ca(2+) signaling. Finally, the combined emission spectra of Ca(2+) and voltage sensitive dyes are compared to allow the choice of the optimum combination to allow simultaneous intracellular Ca(2+) and membrane voltage measurement.
    Methods in cell biology 01/2010; 99:225-61. · 1.44 Impact Factor
  • Ole Johan Kemi, Ulrik Wisloff
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    ABSTRACT: Regular exercise training confers beneficial effects to the heart as well as to the entire body. This occurs partly because exercise training improves skeletal muscle work capacity and reduces resistance, thus increasing conductance in the peripheral circulation. More directly, exercise training also alters extrinsic modulation of the heart and improves the intrinsic pump capacity of the heart. Together, these effects allow for improved exercise capacity. Accumulating evidence suggests that the magnitude of these benefits increases proportionally with the intensity of individual exercise training sessions constituting the exercise training program. It has emerged that regular exercise training also confers beneficial effects to patients at risk for, or who have, established heart dysfunction and disease and, moreover, that exercise training may reduce the dysfunction of the heart itself and, at least, partly restore its ability to effectively function as a pump. The most recent studies in patients with established heart disease suggest that a high relative, yet aerobic, intensity of the exercise training improves the intrinsic pump capacity of the myocardium, an effect not previously believed to occur with exercise training. However, more and larger studies are needed to establish the safety and efficacy of such exercise training in patients with heart disease. Here, we consider the nature of the intensity dependence of exercise training and the causes of the improved heart function.
    Journal of cardiopulmonary rehabilitation and prevention 01/2010; 30(1):2-11. · 1.68 Impact Factor
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    ABSTRACT: This study aims to investigate changes that occur during progression and establishment of physiological and pathological cardiac hypertrophy, by microarray technology and functional annotations. Myocardial infarction leading to heart failure was induced in rats, with animals killed 1, 3, 7, 14, 42, and 92 days after coronary artery ligation. A second group was subjected to daily treadmill exercise and killed 1, 4, 24, and 48 h after a single exercise bout, or after 28 or 56 days of exercise training. Physiological hypertrophy was associated with less transcriptional alternation than pathological hypertrophy, indicating that posttranscriptional and translational regulation may be more important. The main difference between the two types of hypertrophy was that myocardial infarction was associated with downregulation of genes related to fatty acid metabolism, whereas no such change occurred after exercise training. Thus, fatty acid metabolism may distinguish adverse maladaptive hypertrophy from beneficial adaptive hypertrophy. This study points to specific genes and gene classes related to biological processes that may be important in these well-characterized rat models of physiological and pathological cardiac hypertrophy.
    European journal of cardiovascular prevention and rehabilitation: official journal of the European Society of Cardiology, Working Groups on Epidemiology & Prevention and Cardiac Rehabilitation and Exercise Physiology 10/2009; 16(6):690-7. · 2.51 Impact Factor
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    ABSTRACT: In the present study we explored the mechanisms behind excitation-contraction (EC) coupling defects in cardiomyocytes from mice with type-2 diabetes (db/db). We determined whether 13 weeks of aerobic interval training could restore cardiomyocyte Ca(2+) cycling and EC coupling. Reduced contractility in cardiomyocytes isolated from sedentary db/db was associated with increased diastolic sarcoplasmic reticulum (SR)-Ca(2+) leak, reduced synchrony of Ca(2+) release, reduced transverse (T)-tubule density, and lower peak systolic and diastolic Ca(2+) and caffeine-induced Ca(2+) release. Additionally, the rate of SR Ca(2+) ATPase-mediated Ca(2+) uptake during diastole was reduced, whereas a faster recovery from caffeine-induced Ca(2+) release indicated increased Na(+)/Ca(2+)-exchanger activity. The increased SR-Ca(2+) leak was attributed to increased Ca(2+)-calmodulin-dependent protein kinase (CaMKIIdelta) phosphorylation, supported by the normalization of SR-Ca(2+) leak on inhibition of CaMKIIdelta (AIP). Exercise training restored contractile function associated with restored SR Ca(2+) release synchronicity, T-tubule density, twitch Ca(2+) amplitude, SR Ca(2+) ATPase and Na(+)/Ca(2+)-exchanger activities, and SR-Ca(2+) leak. The latter was associated with reduced phosphorylation of cytosolic CaMKIIdelta. Despite normal contractile function and Ca(2+) handling after the training period, phospholamban was hyperphosphorylated at Serine-16. Protein kinase A inhibition (H-89) in cardiomyocytes from the exercised db/db group abolished the differences in SR-Ca(2+) load when compared with the sedentary db/db mice. EC coupling changes were observed without changes in serum insulin or glucose levels, suggesting that the exercise training-induced effects are not via normalization of the diabetic condition. These data demonstrate that aerobic interval training almost completely restored the contractile function of the diabetic cardiomyocyte to levels close to sedentary wild type.
    Circulation Research 09/2009; 105(6):527-36. · 11.09 Impact Factor
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    ABSTRACT: We hypothesized that high-intensity aerobic interval training results in a greater beneficial adaptation of the heart compared with that observed after low-to-moderate exercise intensity. This is supported by recent epidemiological, experimental, and clinical studies. Cellular and molecular mechanisms of myocardial adaptation to exercise training are discussed in this review.
    Exercise and sport sciences reviews 08/2009; 37(3):139-46. · 3.23 Impact Factor

Publication Stats

1k Citations
266.10 Total Impact Points


  • 2006–2013
    • University of Glasgow
      • Institute of Cardiovascular and Medical Sciences
      Glasgow, SCT, United Kingdom
  • 2011
    • University of Michigan
      • Department of Anesthesiology
      Ann Arbor, MI, United States
  • 2010
    • Capital institute of Physical Education
      Peping, Beijing, China
  • 2001–2009
    • Norwegian University of Science and Technology
      • Department of Circulation and Medical Imaging
      Trondheim, Sor-Trondelag Fylke, Norway
  • 2008
    • University Hospital of North Norway
      Tromsø, Troms, Norway
  • 2007
    • St. Olavs Hospital
      Nidaros, Sør-Trøndelag, Norway