Your Heart Can't See What Sneakers You Are Wearing: Exercise Training Load in Endurance Athletes Is Inadequately Quantified in Sports Cardiology: A Systematic Review.

Background: Training load may be an important factor underlying the (patho-)physiologic cardiovascular adaptations from endurance exercise. Yet, quantifying training load remains challenging due to the complexity of its components (Frequency, Intensity, Time, and Type [FITT]). In this systematic review we evaluate how training load has been quantified in sports cardiology studies and provide recommendations for how this can be improved.

Partly Substituting Whey for Collagen Peptide Supplementation Improves Neither Indices of Muscle Damage Nor Recovery of Functional Capacity During Eccentric Exercise Training in Fit Males.

Previous studies showed that collagen peptide supplementation along with resistance exercise enhance muscular recovery and function. Yet, the efficacy of collagen peptide supplementation in addition to standard nutritional practices in athletes remains unclear. Therefore, the objective of the study was to compare the effects of combined collagen peptide (20 g) and whey protein (25 g) supplementation with a similar daily protein dose (45 g) of whey protein alone on indices of muscle damage and recovery of muscular performance during eccentric exercise training.

Exogenous Ketosis Improves Sleep Efficiency and Counteracts the Decline in REM Sleep after Strenuous Exercise.

Introduction: Available evidence indicates that ketone bodies may improve sleep quality. Therefore, we determined whether ketone ester (KE) intake could counteract sleep disruptions induced by strenuous exercise.

Methods: Ten well-trained cyclists with good sleep quality participated in a randomized crossover design consisting of two experimental sessions each involving a morning endurance training and an evening high-intensity interval training ending 1 h before sleep, after which polysomnography was performed overnight.

Exogenous ketosis increases circulating dopamine concentration and maintains mental alertness in ultra-endurance exercise.

Exogenous ketosis can improve psychocognitive functioning during exercise as well as stimulate postexercise muscular recovery. Therefore, we hypothesized that ketone ester (KE) supplementation can counteract the decline in psychocognitive functioning during ultra-endurance exercise and stimulate muscular recovery. Eighteen recreational runners participated in a full 100 km trail run (RUN, = 8), or ran to premature exhaustion (80 km: = 6; 60 km: = 4).

Exogenous ketosis elevates circulating erythropoietin and stimulates muscular angiogenesis during endurance training overload.

De novo capillarization is a primary muscular adaptation to endurance exercise training and is crucial to improving performance. Excess training load, however, impedes such beneficial adaptations, yet we recently demonstrated that such downregulation may be counteracted by ketone ester ingestion (KE) post-exercise. Therefore, we investigated whether KE could increase pro-angiogenic factors and thereby stimulate muscular angiogenesis during a 3-week endurance training-overload period involving 10 training sessions/week in healthy, male volunteers.

Effect of increased protein intake and exogenous ketosis on body composition, energy expenditure and exercise capacity during a hypocaloric diet in recreational female athletes.

Since low body weight is an important determinant of success in many sports such as gymnastics, martial arts and figure skating, athletes can benefit from effective weight loss strategies that preserve muscle mass and athletic performance. The present study investigates the effects of increased protein intake and exogenous ketosis on body composition, energy expenditure, exercise capacity, and perceptions of appetite and well-being during a hypocaloric diet in females. Thirty-two female recreational athletes (age: 22.

Exogenous ketosis suppresses diuresis and atrial natriuretic peptide during exercise.

We have previously demonstrated that exogenous ketosis reduces urine production during exercise. However, the underlying physiological mechanism of this antidiuretic effect remained unclear. Therefore, we investigated whether acute exogenous ketosis by oral ingestion of ketone ester (KE) during a simulated cycling race (RACE) affects the hormonal pathways implicated in fluid balance regulation during exercise.

Exogenous ketosis increases blood and muscle oxygenation but not performance during exercise in hypoxia.

Available evidence indicates that elevated blood ketones are associated with improved hypoxic tolerance in rodents. From this perspective, we hypothesized that exogenous ketosis by oral intake of the ketone ester ()-3-hydroxybutyl ()-3-hydroxybutyrate (KE) may induce beneficial physiological effects during prolonged exercise in acute hypoxia. As we recently demonstrated KE to deplete blood bicarbonate, which per se may alter the physiological response to hypoxia, we evaluated the effect of KE both in the presence and absence of bicarbonate intake (BIC).

Voluntary exercise does not improve muscular properties or functional capacity during C26-induced cancer cachexia in mice.

Exercise training is considered as a potential intervention to counteract muscle degeneration in cancer cachexia. However, evidence to support such intervention is equivocal. Therefore, we investigated the effect of exercise training, i.

Exogenous Ketosis Impairs 30-min Time-Trial Performance Independent of Bicarbonate Supplementation.

Purpose: We recently demonstrated that coingestion of NaHCO3 to counteract ketoacidosis resulting from oral ketone ester (KE) intake improves mean power output during a 15-min time trial (TT) at the end of a 3-h cycling race by ~5%. This ergogenic effect occurred at a time when blood ketone levels were low, as ketosis was only induced during the initial ~2 h of the race. Therefore, in the current study, we investigated whether performance also increases if blood ketone levels are increased in the absence of ketoacidosis during high-intensity exercise.

Sodium bicarbonate improves sprint performance in endurance cycling.

Objectives: Oral sodium bicarbonate intake (NaHCO) may improve performance in short maximal exercise by inducing metabolic alkalosis. However, it remains unknown whether NaHCO also enhances all-out performance at the end of an endurance competition. Therefore, the present study investigated the effect of stacked NaHCO loading on sprint performance following a 3-h simulated cycling race.

Bicarbonate Unlocks the Ergogenic Action of Ketone Monoester Intake in Endurance Exercise.

Purpose: We recently reported that oral ketone ester (KE) intake before and during the initial 30 min of a 3 h 15 min simulated cycling race (RACE) transiently decreased blood pH and bicarbonate without affecting maximal performance in the final quarter of the event. We hypothesized that acid-base disturbances due to KE overrules the ergogenic potential of exogenous ketosis in endurance exercise.

Methods: Nine well-trained male cyclists participated in a similar RACE consisting of 3 h submaximal intermittent cycling (IMT180') followed by a 15-min time trial (TT15') preceding an all-out sprint at 175% of lactate threshold (SPRINT).

Exogenous ketosis impacts neither performance nor muscle glycogen breakdown in prolonged endurance exercise.

Available evidence indicates that ketone bodies inhibit glycolysis in contracting muscles. Therefore, we investigated whether acute exogenous ketosis by oral ketone ester (KE) intake early in a simulated cycling race can induce transient glycogen sparing by glycolytic inhibition, thereby increasing glycogen availability in the final phase of the event. In a randomized crossover design, 12 highly trained male cyclists completed a simulated cycling race (RACE), which consisted of 3-h intermittent cycling (IMT), a 15-min time trial (TT), and a maximal sprint (SPRINT).

Effect of Stacked Sodium Bicarbonate Loading on Repeated All-out Exercise.

The purpose of this study was to evaluate whether NaHCO, administered via a 9-h stacked loading protocol (i.e. repeated supplementation with small doses in order to obtain a gradual increase in blood [HCO ]), has an ergogenic effect on repeated all-out exercise.

Ketone ester supplementation blunts overreaching symptoms during endurance training overload.

Key Points: Overload training is required for sustained performance gain in athletes (functional overreaching). However, excess overload may result in a catabolic state which causes performance decrements for weeks (non-functional overreaching) up to months (overtraining). Blood ketone bodies can attenuate training- or fasting-induced catabolic events.

A noninterfering system to measure in-cage spontaneous physical activity in mice.

Due to lack of low-cost and convenient measurement procedures, uncontrolled changes in spontaneous physical activity (SPA) level often are insufficiently considered as a confounding factor in rodent studies. Nonetheless, alterations in SPA can significantly impact on a wide range of physiological measurements. Therefore, we developed an accurate, low-cost video tracking procedure to allow routine assessment of SPA in the home cage of experimental animals (i.

High-intensity interval training in hypoxia does not affect muscle HIF responses to acute hypoxia in humans.

Purpose: The myocellular response to hypoxia is primarily regulated by hypoxia-inducible factors (HIFs). HIFs thus conceivably are implicated in muscular adaptation to altitude training. Therefore, we investigated the effect of hypoxic versus normoxic training during a period of prolonged hypoxia ('living high') on muscle HIF activation during acute ischaemia.

Physiological Adaptations to Hypoxic vs. Normoxic Training during Intermittent Living High.

In the setting of "living high," it is unclear whether high-intensity interval training (HIIT) should be performed "low" or "high" to stimulate muscular and performance adaptations. Therefore, 10 physically active males participated in a 5-week "live high-train low or high" program (TR), whilst eight subjects were not engaged in any altitude or training intervention (CON). Five days per week (~15.

Intake of a Ketone Ester Drink during Recovery from Exercise Promotes mTORC1 Signaling but Not Glycogen Resynthesis in Human Muscle.

Ketone bodies are energy substrates produced by the liver during prolonged fasting or low-carbohydrate diet. The ingestion of a ketone ester (KE) rapidly increases blood ketone levels independent of nutritional status. KE has recently been shown to improve exercise performance, but whether it can also promote post-exercise muscle protein or glycogen synthesis is unknown.

Twin Resemblance in Muscle HIF-1α Responses to Hypoxia and Exercise.

Hypoxia-inducible factor-1 (HIF-1) is a master regulator of myocellular adaptation to exercise and hypoxia. However, the role of genetic factors in regulation of HIF-1 responses to exercise and hypoxia is unknown. We hypothesized that hypoxia at rest and during exercise stimulates the HIF-1 pathway and its downstream targets in energy metabolism regulation in a genotype-dependent manner.

Physical Activity Counteracts Tumor Cell Growth in Colon Carcinoma C26-Injected Muscles: An Interim Report.

Skeletal muscle tissue is a rare site of tumor metastasis but is the main target of the degenerative processes occurring in cancer-associated cachexia syndrome. Beneficial effects of physical activity in counteracting cancer-related muscle wasting have been described in the last decades. Recently it has been shown that, in tumor xeno-transplanted mouse models, physical activity is able to directly affect tumor growth by modulating inflammatory responses in the tumor mass microenvironment.