Endurance-Trained and Untrained Skeletal Muscle Bioenergetics Observed With Magnetic Resonance Spectroscopy

Bm, Guthrie; Sp, Frostick; J, Goodman; Mikulis, David J.; Mj, Plyley; Kw, Marshall

doi:10.1139/h96-022

Cited by 15 publications

(10 citation statements)

References 14 publications

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“…In contrast, numerous cross-sectional studies reported an elevated PCr/Pi ratio and PCr/ATP ␤ ratios in resistance-trained subjects such as sprinters (44,45) or downhill skiers (46). Conversely, endurance-trained subjects such as long-distance runners (44,45,47) and crosscounty skiers (46) exhibited reduced PCr/Pi and PCr/ATP ␤ ratios as compared to untrained subjects. These findings suggest that the low relative reliability observed previously (20,24) and in the present study was probably due to the homogeneity of individuals regarding fiber type composition.…”

Section: Reliability Of Resting Metabolic Variablesmentioning

confidence: 97%

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A ³¹P‐MRS study

Layec

Bringard²,

Fur

et al. 2009

Magnetic Resonance in Med

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The purpose of the present study was to assess the reliability of metabolic parameters measured using 31 P magnetic resonance spectroscopy ( 31 P MRS) during two standardized rest-exerciserecovery protocols. Twelve healthy subjects performed the standardized protocols at two different intensities; i.e., a moderate intensity (MOD) repeated over a two-month period and heavy intensity (HEAVY) repeated over a year's time. Test-retest reliability was analyzed using coefficient of variation ( Key words: magnetic resonance spectroscopy; reliability; oxidative capacity; PCr kinetics; exercise Phosphorus-31 nuclear magnetic resonance spectroscopy ( 31 P-MRS) is now widely accepted as the "gold standard" method for noninvasive measurements of energy metabolism in exercising muscle. The analysis of changes in phosphorylated compounds concentrations and intracellular pH during rest-exercise-recovery protocols has provided significant advance in the understanding of underlying mechanisms of muscle energy production (1-4). Given the noninvasiveness of the method, 31 P-MRS enables repeated measurements and has been successfully used in a wide range of situations such as the assessment of therapeutic interventions in patients with metabolic disorders (5-7) and the characterization of training-induced metabolic changes (8 -11). More recently, the dynamics of phosphocreatine (PCr) has been used to evaluate the control of mitochondrial respiration in skeletal muscle (12) or the mechanism underlying the V O 2p slow component (13) typically observed during a high-intensity exercise; i.e., above the lactate threshold. In addition, the rate constant of postexercise recovery kinetics of [PCr] has been used as an index of mitochondrial function (14 -17). In addition to these traditional variables, more sophisticated analyses have been put forth in order to quantify the contribution of oxidative and anaerobic pathways to energy production in exercising muscle (2,18,19).Despite the widespread use of 31 P MRS for muscle energetics investigation, the reproducibility of the corresponding variables has been scarcely investigated. It has actually been investigated through repeated measurements performed 1 week (5) and 4 weeks apart (20). Bendahan et al. (5) reported a good reliability in metabolic parameters when investigated using analysis of variance (ANOVA). However, detection of systematic bias might have been affected by large random error between tests as suggested previously (21). observed large test-retest variability in metabolic parameters measured during steady state phases of moderate isometric plantar flexion exercise. However, kinetics parameters of recovery exhibited a small coefficient of variation (CV Ͻ 9%). In this line, van den Broek et al. (22) reported a low variability (CV Ͻ 11.5%) for the parameters describing the recovery kinetics of PCr and adenosine diphosphate (ADP) in a single subject who repeated the same exercise protocol 10 times. Based on a visual inspection of the kinetics of phosphorylated compounds and pH i...

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Section: Reliability Of Resting Metabolic Variablesmentioning

confidence: 97%

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A ³¹P‐MRS study

Layec

Bringard²,

Fur

et al. 2009

Magnetic Resonance in Med

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“…Fiber-type composition was suggested as a potential marker of muscles fitness, as sedentary subjects rely mostly on fast-twitch Type IIb fibers, but, these studies, again, led to contradictory results [83], [84], [89].…”

Section: P-mrs Of Skeletal Musclementioning

confidence: 99%

In-vivo 31P-MRS of skeletal muscle and liver: A way for non-invasive assessment of their metabolism

Valkovič

Chmelík

Krššák

2017

Analytical Biochemistry

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In addition to direct assessment of high energy phosphorus containing metabolite content within tissues, phosphorus magnetic resonance spectroscopy (31P-MRS) provides options to measure phospholipid metabolites and cellular pH, as well as the kinetics of chemical reactions of energy metabolism in vivo. Even though the great potential of 31P-MR was recognized over 30 years ago, modern MR systems, as well as new, dedicated hardware and measurement techniques provide further opportunities for research of human biochemistry. This paper presents a methodological overview of the 31P-MR techniques that can be used for basic, physiological, or clinical research of human skeletal muscle and liver in vivo. Practical issues of 31P-MRS experiments and examples of potential applications are also provided. As signal localization is essential for liver 31P-MRS and is important for dynamic muscle examinations as well, typical localization strategies for 31P-MR are also described.

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“…For resistance trained subjects with high percentage of type-II-fibres such as sprinters [15, 37] or downhill skiers [18], elevated ratios of [PCr]/[P i ] and [PCr]/[ β ATP] have been reported. Conversely, endurance trained subjects which are predominant for type-I-fibres such as long-distance runners [15, 19, 37] or cross-country skiers [18] exhibited reduced values of these parameters. Furthermore, in several animal experiments a correlation between biopsy and 31 P-MRS was observed [13, 38].…”

Section: Discussionmentioning

confidence: 99%

“…31 P-MRS studies in humans demonstrated that athletes with obviously different fibre type composition (e.g., sprinters and long distance runners) feature different 31 P resonance spectra of the resting leg muscles [15–19]. So far, publications correlating biopsy results with the 31 P-MRS measurements in resting human muscles are heterogeneous [17, 20, 21].…”

Section: Introductionmentioning

confidence: 99%

Noninvasive Monitoring of Training Induced Muscle Adaptation with -MRS: Fibre Type Shifts Correlate with Metabolic Changes

Hoff

Brechtel

Strube

et al. 2013

BioMed Research International

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Purpose. To evaluate training induced metabolic changes noninvasively with 31P magnetic resonance spectroscopy (31P-MRS) for measuring muscle fibre type adaptation. Methods. Eleven volunteers underwent a 24-week training, consisting of speed-strength, endurance, and detraining (each 8 weeks). Prior to and following each training period, needle biopsies and 31P-MRS of the resting gastrocnemius muscle were performed. Fibre type distribution was analyzed histologically and tested for correlation with the ratios of high energy phosphates ([PCr]/[Pi], [PCr]/[βATP] and [PCr + Pi]/[βATP]). The correlation between the changes of the 31P-MRS parameters during training and the resulting changes in fibre composition were also analysed. Results. We observed an increased type-II-fibre proportion after speed-strength and detraining. After endurance training the percentage of fast-twitch fibres was reduced. The progression of the [PCr]/[Pi]-ratio was similar to that of the fast-twitch fibres during the training. We found a correlation between the type-II-fibre proportion and [PCr]/[Pi] (r = 0.70, P < 0.01) or [PCr]/[βATP] (r = 0.69, P < 0.01); the correlations between its changes (delta) and the fibre-shift were significant as well (delta[PCr]/[Pi] r = 0.66, delta[PCr]/[βATP] r = 0.55, P < 0.01). Conclusion. Shifts in fibre type composition and high energy phosphate metabolite content covary in human gastrocnemius muscle. Therefore 31P-MRS might be a feasible method for noninvasive monitoring of exercise-induced fibre type transformation.

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Endurance-Trained and Untrained Skeletal Muscle Bioenergetics Observed With Magnetic Resonance Spectroscopy

Cited by 15 publications

References 14 publications

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A ³¹P‐MRS study

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A ³¹P‐MRS study

In-vivo 31P-MRS of skeletal muscle and liver: A way for non-invasive assessment of their metabolism

Noninvasive Monitoring of Training Induced Muscle Adaptation with -MRS: Fibre Type Shifts Correlate with Metabolic Changes

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Endurance-Trained and Untrained Skeletal Muscle Bioenergetics Observed With Magnetic Resonance Spectroscopy

Cited by 15 publications

References 14 publications

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A 31P‐MRS study

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A 31P‐MRS study

In-vivo 31P-MRS of skeletal muscle and liver: A way for non-invasive assessment of their metabolism

Noninvasive Monitoring of Training Induced Muscle Adaptation with -MRS: Fibre Type Shifts Correlate with Metabolic Changes

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Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A ³¹P‐MRS study

Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A ³¹P‐MRS study