PMID- 38537252
OWN - NLM
STAT- Publisher
LR  - 20240327
IS  - 1530-0315 (Electronic)
IS  - 0195-9131 (Linking)
DP  - 2024 Mar 25
TI  - Five Weeks of Sprint Interval Training Improve Muscle Glycolytic Content and 
      Activity But Not Time to Task Failure in Severe Intensity Exercise.
LID - 10.1249/MSS.0000000000003425 [doi]
AB  - PURPOSE: This study examined the impact of a 5 weeks 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 weeks, or a 
      control group (n = 6). At pre-training 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. After 5 
      weeks, the same evaluations were repeated (i.e., exercise intensities matched to 
      current training status), and an additional cycling CWR matched to pre-training 
      150% RCP-PO was performed only for TTF evaluation. The content and enzymatic 
      activity of glycogen phosphorylase (GPhos), hexokinase (HK), phosphofructokinase 
      (PFK), and lactate dehydrogenase (LDH), as well as the glycogen content, were 
      analyzed. Content of monocarboxylate transporter isoform 4 (MCT4) and muscle 
      buffering capacity were also measured. RESULTS: Despite improvements in total 
      work performed at CWR post-training, no differences were observed for TTF. The 
      GPhos, HK, PFK, and LDH content and activity, and glycogen content also improved 
      post-training only in the SIT group. Further, the MCT4 concentrations and muscle 
      buffering capacity was also improved only for SIT group. However, no difference 
      in glycogen depletion was observed between groups and time. CONCLUSIONS: Five 
      weeks of SIT improved the glycolytic pathway parameters and total work performed, 
      however, glycogen depletion was not altered during CWR severe intensity exercise, 
      and TTF remained similar.
CI  - Copyright (c) 2024 by the American College of Sports Medicine.
FAU - de Araujo Bonetti de Poli, Rodrigo
AU  - de Araujo Bonetti de Poli R
AD  - Laboratory of Physiology and Sport Performance (LAFIDE), Graduate Program in 
      Movement Sciences, Sao Paulo State University (UNESP), School of Sciences. Bauru, 
      BRAZIL.
FAU - Murias, Juan Manuel
AU  - Murias JM
AD  - College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, QATAR.
FAU - Antunes, Barbara Moura
AU  - Antunes BM
FAU - Marinari, Gabriele
AU  - Marinari G
AD  - Faculty of Kinesiology, University of Calgary, Calgary, Alberta, CANADA.
FAU - Dutra, Yago Medeiros
AU  - Dutra YM
AD  - Laboratory of Physiology and Sport Performance (LAFIDE), Graduate Program in 
      Movement Sciences, Sao Paulo State University (UNESP), School of Sciences. Bauru, 
      BRAZIL.
FAU - Milioni, Fabio
AU  - Milioni F
AD  - Centro Universitario Nossa Senhora do Patrocinio, Itu, BRAZIL.
FAU - Zagatto, Alessandro Moura
AU  - Zagatto AM
AD  - Laboratory of Physiology and Sport Performance (LAFIDE), Graduate Program in 
      Movement Sciences, Sao Paulo State University (UNESP), School of Sciences. Bauru, 
      BRAZIL.
LA  - eng
PT  - Journal Article
DEP - 20240325
PL  - United States
TA  - Med Sci Sports Exerc
JT  - Medicine and science in sports and exercise
JID - 8005433
SB  - IM
COIS- Conflict of Interest and Funding Source: RABP, YMD and AMZ received Sao Paulo 
      Research Foundation (FAPESP) grants (Process number # 19/17445-1; # 21/08479-0; 
      #18/21126-6, respectively). In addition, this work was supported by the National 
      Council for Scientific and Technological Development (CNPq)-Brazil, [Grant No. 
      422193/2016-0].
EDAT- 2024/03/28 00:45
MHDA- 2024/03/28 00:45
CRDT- 2024/03/27 18:23
PHST- 2024/03/28 00:45 [medline]
PHST- 2024/03/28 00:45 [pubmed]
PHST- 2024/03/27 18:23 [entrez]
AID - 00005768-990000000-00489 [pii]
AID - 10.1249/MSS.0000000000003425 [doi]
PST - aheadofprint
SO  - Med Sci Sports Exerc. 2024 Mar 25. doi: 10.1249/MSS.0000000000003425.