PMID- 22138866
OWN - NLM
STAT- MEDLINE
DCOM- 20121129
LR  - 20211021
IS  - 1439-6327 (Electronic)
IS  - 1439-6319 (Linking)
VI  - 112
IP  - 8
DP  - 2012 Aug
TI  - The effects of carbohydrate intake and muscle glycogen content on self-paced 
      intermittent-sprint exercise despite no knowledge of carbohydrate manipulation.
PG  - 2859-70
LID - 10.1007/s00421-011-2253-0 [doi]
AB  - The aim of this study was to determine the effects of carbohydrate (CHO) 
      ingestion and muscle glycogen content, without the influence of knowledge of CHO 
      consumption, on intermittent-sprint performance. Ten males completed two 
      conditions on two consecutive days. Day 1 involved 2 x 40 min of leg cycling 
      separated by 15 min of arm cycling, followed by an overnight diet consuming 
      either a high [HCHO; 7 g/kg body weight (bw)] or low (LCHO; 2 g/kg bw) CHO diet. 
      Participants were blinded to the knowledge CHO was being examined or manipulated. 
      Day 2 included a 60-min intermittent-sprint exercise (ISE) protocol that included 
      15-m maximal sprints every minute and self-paced efforts of varying intensities. 
      Pre and post-ISE muscle biopsies were obtained on Day 2. Pre- and post-exercise 
      maximal voluntary torque (MVT), voluntary activation (VA) and twitch contractile 
      properties were assessed during 15 maximal isometric contractions. Blood glucose 
      and lactate, heart rate (HR) and rating of perceived exertion (RPE) were also 
      recorded. Pre-ISE muscle glycogen was greater in HCHO compared with LCHO 
      (597 +/- 115 vs. 318 +/- 72 mmol kg dry weight; P = 0.001). Total distance and hard 
      running distance were 4.9 and 8.1% greater in HCHO, respectively (P = 0.02-0.04). 
      Peak MVT, VA, HR and RPE were not different between conditions (P > 0.05). Blood 
      glucose was higher pre-ISE for LCHO but lower post-ISE compared with HCHO 
      (P < 0.05). These results indicate HCHO improved self-paced exercise intensities 
      during the ISE protocol despite no knowledge of dietary manipulation. Due to the 
      blinded study design, exercise intensities seem manipulated due to peripheral 
      perturbations associated with CHO content rather than a conscious manipulation of 
      exercise intensities.
FAU - Skein, Melissa
AU  - Skein M
AD  - School of Human Movement Studies, Charles Sturt University, Bathurst, NSW, 2795, 
      Australia. mskein@csu.edu.au
FAU - Duffield, Rob
AU  - Duffield R
FAU - Kelly, Bradley T
AU  - Kelly BT
FAU - Marino, Frank E
AU  - Marino FE
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
DEP - 20111203
PL  - Germany
TA  - Eur J Appl Physiol
JT  - European journal of applied physiology
JID - 100954790
RN  - 0 (Blood Glucose)
RN  - 0 (Dietary Carbohydrates)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 9005-79-2 (Glycogen)
SB  - IM
MH  - Analysis of Variance
MH  - Biomechanical Phenomena
MH  - Biopsy
MH  - Blood Glucose/metabolism
MH  - *Diet, Carbohydrate-Restricted
MH  - Dietary Carbohydrates/administration & dosage/*metabolism
MH  - Double-Blind Method
MH  - *Exercise
MH  - Exercise Test
MH  - Glycogen/*metabolism
MH  - Heart Rate
MH  - Humans
MH  - *Isometric Contraction
MH  - Lactic Acid/blood
MH  - Male
MH  - Muscle, Skeletal/*metabolism
MH  - New South Wales
MH  - Oxygen Consumption
MH  - Perception
MH  - *Running
MH  - Task Performance and Analysis
MH  - Time Factors
MH  - Torque
EDAT- 2011/12/06 06:00
MHDA- 2012/12/10 06:00
CRDT- 2011/12/06 06:00
PHST- 2011/08/11 00:00 [received]
PHST- 2011/11/15 00:00 [accepted]
PHST- 2011/12/06 06:00 [entrez]
PHST- 2011/12/06 06:00 [pubmed]
PHST- 2012/12/10 06:00 [medline]
AID - 10.1007/s00421-011-2253-0 [doi]
PST - ppublish
SO  - Eur J Appl Physiol. 2012 Aug;112(8):2859-70. doi: 10.1007/s00421-011-2253-0. Epub 
      2011 Dec 3.