ﻣﻘﺎﯾﺴﮥ اﺛﺮ زﻣﺎنﻫﺎي ﻣﺘﻔﺎوت ﻣﺼﺮف ﮐﺮﺑﻮﻫﯿﺪرات ﻗﺒﻞ از ﻓﻌﺎﻟﯿﺖ ورزﺷﯽ ﺑﺮ MFO و Fatmax در دوﻧﺪﮔﺎن اﺳﺘﻘﺎﻣﺘﯽ

Comparison of Different Timing Effect of Carbohydrate Intake Before Exercise on MFO and Fatmax in Endurance Runners

ﻫﺪف از ﭘﮋوﻫﺶ ﺣﺎﺿﺮ ﻣﻘﺎﯾﺴﮥ اﺛﺮ زﻣﺎنﻫﺎي ﻣﺘﻔﺎوت ﻣﺼﺮف ﮐﺮﺑﻮﻫﯿﺪرات ﻗﺒﻞ از ﻓﻌﺎﻟﯿﺖ ورزﺷﯽ ﺑﺮ ﺑﯿﺸﯿﻨﮥ اﮐﺴﯿﺪاﺳﯿﻮن ﭼﺮﺑﯽ و ﺷﺪﺗﯽ از ﻓﻌﺎﻟﯿﺖ ﮐﻪ ﺑﯿﺸﯿﻨﮥ اﮐﺴﯿﺪاﺳﯿﻮن ﭼﺮﺑﯽ در آن رخ ﻣﯽدﻫﺪ (Fatmax) در دوﻧﺪﮔﺎن اﺳﺘﻘﺎﻣﺘﯽ ﺑﻮد. در اﯾﻦ ﭘﮋوﻫﺶ ﻫﺸﺖ دوﻧﺪة اﺳﺘﻘﺎﻣﺘﯽ ﺣﺮﻓﻪاي (ﺑﺎ ﻣﯿﺎﻧﮕﯿﻦ ﺳﻨﯽ2/61±21/6 ﺳﺎل؛ ﺣﺪاﮐﺜﺮ اﮐﺴﯿﮋن ﻣﺼﺮﻓﯽ 8/7±63/0 ﻣﯿﻠﯽﻟﯿﺘﺮ ﺑﺮ ﮐﯿﻠﻮﮔﺮم در دﻗﯿﻘﻪ؛ درﺻﺪ ﭼﺮﺑﯽ ﺑﺪن 1/92±9/1 درﺻﺪ؛ ﺳﺎﺑﻘﮥ ورزﺷﯽ 7±3 ﺳﺎل) ﺑﻪﻋﻨﻮان آزﻣﻮدﻧﯽ در ﭼﻬﺎر آزﻣﻮن ﺟﺪاﮔﺎﻧﻪ ﺷﺮﮐﺖ ﻧﻤﻮدﻧﺪ. در ﺟﻠﺴﮥ اول، آزﻣﻮدﻧﯽﻫﺎ ﺳﺎﻋﺖ ﻫﺸﺖ ﺻﺒﺢ و درﺣﺎﻟﺖ ﻧﺎﺷﺘﺎ، آزﻣﻮن ﻓﻌﺎﻟﯿﺖ ورزﺷﯽ ﻓﺰاﯾﻨﺪه )ﺷﺎﻣﻞ ﻓﻌﺎﻟﯿﺖ روي ﻧﻮارﮔﺮدان ﺗﺎ ﻣﺮﺣﻠﮥ ﺧﺴﺘﮕﯽ( را ﺑﻪﻣﻨﻈﻮر ﺗﻌﯿﯿﻦ ﻣﯿﺰان ﺑﯿﺸﯿﻨﮥ اﮐﺴﯿﺪاﺳﯿﻮن ﭼﺮﺑﯽ وFatmax اﻧﺠﺎم دادﻧﺪ. در ﺟﻠﺴﮥ دوم، ﺳﻮم و ﭼﻬﺎرم ﻧﯿﺰ ﺑﺎ ﻓﺎﺻﻠﮥ ﻫﻔﺖ ﺗﺎ 10 روز، آزﻣﻮدﻧﯽﻫﺎ درﺣﺎﻟﺖ ﻧﺎﺷﺘﺎ، ﻣﻘﺪار ﯾﮏ ﮔﺮم ﮔﻠﻮﮐﺰ ﺑﻪازاي ﻫﺮﮐﯿﻠﻮﮔﺮم وزن ﺑﺪن ﺑﻪﻫﻤﺮاه 500 ﻣﯿﻠﯽﻟﯿﺘﺮ آب را در ﻓﻮاﺻﻞ ﭘﻨﺞ دﻗﯿﻘﻪ، ﯾﮏ ﺳﺎﻋﺖ و ﺳﻪ ﺳﺎﻋﺖ ﻗﺒﻞ از ﺷﺮوع آزﻣﻮن ﻓﺰاﯾﻨﺪه ﻣﺼﺮف ﻧﻤﻮدﻧﺪ. ﻣﻘﺪار ﺑﯿﺸﯿﻨﮥ اﮐﺴﯿﺪاﺳﯿﻮن ﭼﺮﺑﯽ وFatmax از ﻃﺮﯾﻖ روش ﮐﺎﻟﺮيﺳﻨﺠﯽ ﻏﯿﺮﻣﺴﺘﻘﯿﻢ ﺑﺎ اﺳﺘﻔﺎده از دﺳﺘﮕﺎه ﮔﺎزآﻧﺎﻻﯾﺰر ﺑﺎ ﮐﻤﮏ ﻣﻌﺎدﻻت ﻋﻨﺼﺮﺳﻨﺠﯽ اﻧﺪازهﮔﯿﺮي ﮔﺮدﯾﺪ و آزﻣﻮن ﺗﺠﺰﯾﻪوﺗﺤﻠﯿﻞ وارﯾﺎﻧﺲ ﺑﺎ اﻧﺪازهﮔﯿﺮيﻫﺎي ﻣﮑﺮر ﺑﺮاي ﺗﺠﺰﯾﻪوﺗﺤﻠﯿﻞ آﻣﺎري ﻣﻮرد اﺳﺘﻔﺎده ﻗﺮار ﮔﺮﻓﺖ. زﻣﺎﻧﯽﮐﻪ ﮐﺮﺑﻮﻫﯿﺪرات، ﭘﻨﺞ دﻗﯿﻘﻪ و ﯾﮏ ﺳﺎﻋﺖ ﻗﺒﻞ از اﺟﺮاي ﻓﻌﺎﻟﯿﺖ ورزﺷﯽ ﻣﺼﺮف ﺷﺪه ﺑﻮد، ﺑﯿﺸﯿﻨﮥ اﮐﺴﯿﺪاﺳﯿﻮن ﭼﺮﺑﯽ و Fatmax ﺑﻪﺗﺮﺗﯿﺐ ﮐﻤﺘﺮﯾﻦ و ﺑﯿﺸﺘﺮﯾﻦ ﮐﺎﻫﺶ را ﻧﺸﺎن ﻣﯽداد. ﻫﻤﭽﻨﯿﻦ، ﺑﯿﺸﯿﻨﮥ اﮐﺴﯿﺪاﺳﯿﻮن ﭼﺮﺑﯽ و Fatmax در وﺿﻌﯿﺖ ﻧﺎﺷﺘﺎ ﺑﻪﻃﻮر ﻣﻌﻨﺎداري ﻧﺴﺒﺖ ﺑﻪ وﺿﻌﯿﺖ ﻣﺼﺮف ﮐﺮﺑﻮﻫﯿﺪرات در ﻓﻮاﺻﻞ ﭘﻨﺞ دﻗﯿﻘﻪ، ﯾﮏ ﺳﺎﻋﺖ و ﺳﻪ ﺳﺎﻋﺖ ﻗﺒﻞ از ﻓﻌﺎﻟﯿﺖ ورزﺷﯽ ﺑﺎﻻﺗﺮ ﺑﻮد )0.05

The aim of this study was to compare of different timing effect of carbohydrate intake before exercise on maximal fat oxidation (MFO) and Fatmax in endurance runners. Eight professional endurance runners (age 21.6±2.61 years, VO2max 63.0±8.7 ml.kg.min, body fat percentage 9.1±1.92, Background 7±3 years) participated as the subject in four separate trials. In the first session, the participants performed a graded exercise tests at 8 a.m. in fasted condition on treadmill to exhaustion in order to determine the amount of Fatmax and MFO. In the second, third and fourth session, with an interval of seven to ten days, participants in fasted condition, consumed 1 gr carbohydrate per kg body weight, with 500 ml water five minutes, one and three hours before the beginning of graded exercise tests. The amount of MFO and Fatmax were measured through indirect calorimetry method using the gas analysis system with aim of stoichiometric equation. The analysis of variance tests with repeated measures was used for data analysis. When carbohydrate is consumed five minutes and one hour prior to physical activity, MFO and Fatmax depict the lowest and highest decline respectively. MFO and Fatmax, in fasted condition, was significantly higher than the consumption of carbohydrate five minutes, one hour and three hours before the exercise (P<0.05). But no significant difference was seen in MFO and fatmax between different conditions of carbohydrate consumption. In general, the results indicated that consumption of carbohydrate in different timings before exercise cause the decrease in MFO and transferring of Fatmax to lower intensity of exercise. This means that the start of fat oxidation reduction occurs in lower intensity and participants depend more on carbohydrate sources.