Comparison of metabolic adaptations between endurance‐ and sprint‐trained athletes after an exhaustive exercise in two different calf muscles using a multi‐slice ³¹P‐MR spectroscopic sequence

Abstract

Measurements of exercise-induced metabolic changes, such as oxygen consumption, carbon dioxide exhalation or lactate concentration, are important indicators for assessing the current performance level of athletes in training science. With exercise-limiting metabolic processes occurring in loaded muscles, P-MRS represents a particularly powerful modality to identify and analyze corresponding training-induced alterations. Against this background, the current study aimed to analyze metabolic adaptations after an exhaustive exercise in two calf muscles (m. soleus - SOL - and m. gastrocnemius medialis - GM) of sprinters and endurance athletes by using localized dynamic P-MRS. In addition, the respiratory parameters VO and VCO , as well as blood lactate concentrations, were monitored simultaneously to assess the effects of local metabolic adjustments in the loaded muscles on global physiological parameters. Besides noting obvious differences between the SOL and the GM muscles, we were also able to identify distinct physiological strategies in dealing with the exhaustive exercise by recruiting two athlete groups with opposing metabolic profiles. Endurance athletes tended to use the aerobic pathway in the metabolism of glucose, whereas sprinters produced a significantly higher peak concentration of lactate. These global findings go along with locally measured differences, especially in the main performer GM, with sprinters revealing a higher degree of acidification at the end of exercise (pH 6.29 ± 0.20 vs. 6.57 ± 0.21). Endurance athletes were able to partially recover their PCr stores during the exhaustive exercise and seemed to distribute their metabolic activity more consistently over both investigated muscles. In contrast, sprinters mainly stressed Type II muscle fibers, which corresponds more to their training orientation preferring the glycolytic energy supply pathway. In conclusion, we were able to analyze the relation between specific local metabolic processes in loaded muscles and typical global adaptation parameters, conventionally used to monitor the training status of athletes, in two cohorts with different sports orientations.

Resilience in the Endurance Runner: The Role of Self-Regulatory Modes and Basic Psychological Needs

“…Endurance performances are defined as performances during whole-body, dynamic exercise that involves continuous effort and lasts for 75 s or longer (McCormick et al, 2015). Endurance athletes differ from sprint-trained athletes and strength athletes with respect to metabolic adaptation and also with respect to the psychological mechanism highlighting their performances (Moll et al, 2018;Degens et al, 2019;Guicciardi et al, 2019).…”

Age-related Decline in Renal Function is Attenuated in Master Athletes

“…In this regard, cystatin C equation proposed by Larson et al [25] may better explain the eGFR in this specific population once endurance athletes partially recover their phosphocreatine stores during exercise [30]. However, sprinters often present higher muscle mass, and predominantly stress mainly type II muscle fibers during training sessions, which corresponds more to the glycolytic and purine energy supply pathway leading to an increased excretion of phosphocreatine [18,30,31]. Therefore, the higher levels of creatinine in SA participants observed in the present study might be Data are presented as means and standard deviation.…”

“…However, creatinine is sensitive to the environment and muscle mass once it can be increased as far as the exercise intensity increases [28,29]. In this regard, cystatin C equation proposed by Larson et al [25] may better explain the eGFR in this specific population once endurance athletes partially recover their phosphocreatine stores during exercise [30]. However, sprinters often present higher muscle mass, and predominantly stress mainly type II muscle fibers during training sessions, which corresponds more to the glycolytic and purine energy supply pathway leading to an increased excretion of phosphocreatine [18,30,31].…”

Energy Expenditure of Dynamic Submaximal Human Plantarflexion Movements: Model Prediction and Validation by in-vivo Magnetic Resonance Spectroscopy

“…The movements were identical as in experiment 2. An in-house developed 31 P-MRS pulse sequence, dubbed MUSCLE (MUlti SliCe Localized Excitation (Moll et al, 2018); TR = 5,000 ms; flip angle: 50 • ; acquisition delay between excitation RF pulse and acquisition: 1.3 ms; excitation pulse duration/bandwidth: 1, 600 µs/2.5 kHz), was used to acquire series of 360 single 31 P-MR spectra in a 16 mm thick slice covering the M. gastrocnemius medialis (see Figure 3 for slice positions). In an entire 31 P-MR spectra series (see the right chart of Figure 3), 24 spectra were measured during rest (2 min), followed by the acquisition of 36 spectra during load (3 min), and 300 spectra during recovery (25 min).…”