The
Glycemic Index of the carbohydrates consumed in a sports drink
or beverage determines metabolic response during exercise.
So, choosing the right sports drink/beverage has a profound
on sports performance.
High
Glycemic Carbs Result in
Reduced Exercise Capacity
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In
a clinical study of 1000 athletes, elevated blood sugar levels
result in reduced exercise capacity and reduced sports performance.
Differences in clinical characteristics, exercise hemodynamics,
perfusion imaging, and univariate as well as multivariate
predictors of exercise capacity were determined(1).
Maximum
oxygen consumption (VO2max/maximum oxygen consumption) and
maximal watts were also measured.
The trial results showed that subjects with impaired fasting
glucose or elevated blood glucose levels (126 mg/dl), experience
lower VO2max and lower peak watts.
Imbalanced blood glucose levels are triggered by drinking
High Glycemic sports drinks and beverages. This includes beverages
containing High Glycemic carbohydrates, such as sucrose, and/or
High Fructose Corn Syrup, Glucose, Agave, and/or Maltodextrins,
as well as beverages that do not contain any carbohydrates
or calories (High Cephalic), such as diet sodas, and sports
drinks that claim -0- calories/carbs.
High Glycemic and High Cephalic beverages can also cause Reactive
Hypoglycemia (low blood sugar), which impairs sports performance.
Consuming a High Glycemic or High Cephalic index beverage
less than an hour prior to an athletic event can cause hypoglycemia
at the start of the event, which drastically reduces sports
performance and endurance.
Low
Glycemic Index Beverages Improves Recovery from Prolonged
Exercise
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Low
Glycemic Time-To-Exhaustion
Benefits Evidenced in Endurance Capacity
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The Low Glycemic Index of a sports drink or beverage determines
endurance capacity and time-to-exhaustion in active humans.
Subjects running for 90 minutes at 70% VO2max ingested Low
Glycemic Index carbohydrates (8g CHO/kg body mass) vs High
Glycemic Index carbohydrates.
Time-to-exhaustion during was longer in the Low Glycemic Index
trial (108.9 +/- 7.4 min) than in the HGI trial (96.9 +/-
4.8 min).
Fat-oxidation (fat-burning) rates and free fatty acid concentrations
were higher in the Low Glycemic Index trial than the High
Glycemic Index trial.
Increased endurance capacity is a primary consequence of increased
fat-oxidation following ingestion of a Low Glycemic sports
drink/beverage.
Sports drinks and beverages containing Low Glycemic Index
carbohydrates with a Low Glycemic Index (GI) maintain balanced
and sustained blood glucose release and fat-oxidation, which
spares muscle glycogen. The lower the Glycemic Index of the
drink, the better blood glucose is sustained. In pre-event
fueling, this is essential.
CONCLUSIONS
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The
vast majority of sports drinks and functional beverages
on the market are high glycemic |
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High
glycemic sports drinks overly-elevate blood glucose
levels and reduce endurance capacity and fat-oxidation |
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Exercise capacity is tied to blood glucose levels |
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Elevated blood glucose levels impairs sports performance |
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Reduced
sports performance is directly tied to ingestion of
High Glycemic sports drinks and beverages |
Copyright
© 2008 Human Sports Performance® (HSP) |
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