Neural and Muscular Determinants of Performance Fatigability Are Independent of Work and Recovery Durations During High-Intensity Interval Exercise in Males.

The present study aimed to investigate the effect of two protocols of high-intensity interval exercise (HIIE) on performance fatigability and its neural and muscular determinants. On different days, 14 healthy males performed two HIIE protocols with different work and recovery durations (matched for total duration, work and recovery intensities, and density): 1) 4 × 4 min at 90% HR,180-s recovery at 70% HR; and 2) 16 × 1 min at 90% HR, 45-s recovery at 70% HR. Pre- to post-HIIE reduction in maximal voluntary isometric contraction (MVIC) was used as marker of performance fatigability, while voluntary activation (VA) and potentiated quadriceps twitch force (Q) as markers of the neural (i.

Airflow restriction mask induces greater central fatigue after a non-exhaustive high-intensity interval exercise.

The airflow restriction mask (ARM) is a practical and inexpensive device for respiratory muscle training. Wearing an ARM has recently been combined with high-intensity interval exercise (HIIE), but its effect on neuromuscular fatigue is unknown. The present study investigated the effects of ARM wearing on neuromuscular fatigue after an HIIE session.

Extract Increases Oxygen Uptake without Changes in Neuromuscular Fatigue Development during a High-Intensity Interval Exercise.

Objective: We investigated the effects of acute ingestion of extract on metabolic and cardiopulmonary responses during a high-intensity interval exercise (HIIE), and its consequence on neuromuscular fatigue.

Methods: Ten healthy men underwent a HIIE (4 x 4 min, 3 min recovery) one hour after ingesting 400 mg of extract (MIE) or placebo. Oxygen uptake (O), dioxide carbon production (CO), ventilation (E) and heart rate (HR) were measured throughout the HIIE.

Caffeine increases peripheral fatigue in low- but not in high-performing cyclists.

The influence of cyclists' performance levels on caffeine-induced increases in neuromuscular fatigue after a 4-km cycling time trial (TT) was investigated. Nineteen cyclists performed a 4-km cycling TT 1 h after ingesting caffeine (5 mg·kg) or placebo (cellulose). Changes from baseline to after exercise in voluntary activation (VA) and potentiated 1 Hz force twitch () were used as markers of central and peripheral fatigue, respectively.

Relationship between recovery of neuromuscular function and subsequent capacity to work above critical power.

Purpose: To investigate the relationship between the recovery of neuromuscular fatigue and the recovery of amount of work done above critical power (W´).

Methods: Ten healthy men performed, on different days, constant work rate exercises until task failure to determine critical power (CP) and W´. In the three following visits, participants performed two exhausting constant work rate exercises estimated to induce task failure within 6 min (P6 and P6), interspaced by 3, 6 or 15 min of recovery.

Correction: Effect of caffeine on neuromuscular function following eccentric-based exercise.

[This corrects the article DOI: 10.1371/journal.pone.

Effect of caffeine on neuromuscular function following eccentric-based exercise.

This study investigated the effect of caffeine on neuromuscular function, power and sprint performance during the days following an eccentric-based exercise. Using a randomly counterbalanced, crossover and double-blinded design, eleven male jumpers and sprinters (age: 18.7 ± 2.

The Effects of Acute and Chronic Sprint-Interval Training on Cytokine Responses Are Independent of Prior Caffeine Intake.

We examined the effect of acute and chronic sprint interval training (SIT), with or without prior caffeine intake, on levels of exercise-induced inflammatory plasma cytokines [interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α]. Twenty physically-active men ingested either a placebo ( = 10) or caffeine ( = 10) 1 h before each SIT session(13-s × 30-s sprint/15 s of rest) during six training sessions (2 weeks). The early (before, immediately after, and 45 min after the exercise) and late (24 and 48 h after the exercise) cytokine and creatine kinase (CK) responses were analyzed for the first and last training sessions.

Arterialized and venous blood lactate concentration difference during different exercise intensities.

Objective: The purpose of this study was to investigate the difference between arterialized and venous blood lactate concentrations [La] during constant-load exercises at different intensities.

Methods: Fifteen physically active men cycled for 30 minutes (or until exhaustion) at the first lactate threshold (LT), at 50% of the difference between the first and second lactate threshold (TT), at the second lactate threshold (LT), and at 25% of the difference between LT and maximal aerobic power output (TW). Samples of both arterialized and venous blood were collected simultaneously at rest and every 5 minutes during the exercise.

Caffeine increases both total work performed above critical power and peripheral fatigue during a 4-km cycling time trial.

The link between total work performed above critical power (CP) and peripheral muscle fatigue during self-paced exercise is unknown. We investigated the influence of caffeine on the total work done above CP during a 4-km cycling time trial (TT) and the subsequent consequence on the development of central and peripheral fatigue. Nine cyclists performed three constant-load exercise trials to determine CP and two 4-km TTs ~75 min after oral caffeine (5 mg/kg) or cellulose (placebo) ingestion.

Separate and Combined Effects of Caffeine and Sodium-Bicarbonate Intake on Judo Performance.

Unlabelled: The combined supplementation of caffeine (CAF) and sodium bicarbonate (NaHCO3) may have a potential ergogenic effect during intermittent-exercise tasks such as judo; however, its effect in this sport has not been tested.

Purpose: To investigate the isolated and combined effects of CAF and NaHCO3 on judo performance.

Methods: Ten judokas performed 4 supplementation protocols-NaHCO3, CAF, NaHCO3 + CAF, and placebo (PLA) (cellulose)-followed by 3 Special Judo Fitness Tests (SJFTs) interspaced with 5 min rest.