Is the time to task failure during severe intensity exercise associated with muscle, blood, and respiratory changes?

The study aimed to verify the physiological and metabolic parameters associated with the time to task failure (TTF) during cycling exercise performed within the severe-intensity domain. Forty-five healthy and physically active males participated in two independent experiments. In experiment 1, after a graded exercise test, participants underwent constant work rate cycling efforts (CWR) at 115% of peak power output to assess neuromuscular function (Potentiated twitch) pre- and post-exercise.

β-Alanine Plus Sodium Bicarbonate Co-Supplementation Does Not Decrease Neuromuscular Fatigue in Swimming.

This study aimed to investigate the effects of chronic β-alanine (βA) plus acute sodium bicarbonate (SB) co-supplementation on neuromuscular fatigue during high-intensity intermittent efforts in swimming. Eleven regional and national competitive-level young swimmers performed a neuromuscular fatigue assessment before and immediately after two 20 × 25-m front crawl maximal efforts every 90 s, performed at pre- and post-4-week co-supplementation. Neuromuscular fatigue was evaluated by percutaneous electrical stimuli through the twitch interpolation technique on the and .

Heavy-intensity priming exercise extends the V̇o plateau and increases peak-power output during ramp-incremental exercise.

This study investigated whether a heavy-intensity priming exercise precisely prescribed within the heavy-intensity domain would lead to a greater peak-power output (PO) and a longer maximal oxygen uptake (V̇o) plateau. Twelve recreationally active adults participated in this study. Two visits were required: ) a step-ramp-step test [ramp-incremental (RI) control], and ) an RI test preceded by a priming exercise within the heavy-intensity domain (RI primed).

Five Weeks of Sprint Interval Training Improve Muscle Glycolytic Content and Activity But Not Time to Task Failure in Severe-Intensity Exercise.

Purpose: This study examined the impact of a 5-wk sprint interval training (SIT) intervention on time to task failure (TTF) during severe-intensity constant work rate (CWR) exercise, as well as in glycolytic enzymatic content and activity, and glycogen content.

Methods: Fourteen active males were randomized into either a SIT group ( n = 8) composed of 15 SIT sessions over 5 wk, or a control group ( n = 6). At pretraining period, participants performed i) ramp incremental test to measure the cardiorespiratory function; ii) CWR cycling TTF at 150% of the power output (PO) at the respiratory compensation point (RCP-PO) with muscle biopsies at rest and immediately following task failure.

A Ramp versus Step Transition to Constant Work Rate Exercise Decreases Steady-State Oxygen Uptake.

Purpose: This study aimed to investigate whether a ramp-to-constant WR (rCWR) transition compared with a square-wave-to-constant WR (CWR) transition within the heavy-intensity domain can reduce metabolic instability and decrease the oxygen cost of exercise.

Methods: Fourteen individuals performed (i) a ramp-incremental test to task failure, (ii) a 21-min CWR within the heavy-intensity domain, and (iii) an rCWR to the same WR. Oxygen uptake (V̇O 2 ), lactate concentration ([La - ]), and muscle oxygen saturation (SmO 2 ) were measured.