Bentnose wrote:According to my Hi-5 Energy source carbohydrates can only be absorbed into the bloostream at a rate of 60g and hour unless you use the Energysource fructose mix which allows 90g an hour.
As far as I remember, provided glycogen stores are full, low to medium intensity excercise up to 1.5 hours should okay without energy drinks after that .5g per kg of body weight per hour. High intensity excercise, eg. racing, 1g per kg of body weight. Recovery is to be 2g per Kg of body weight per hour raced. For 1.5 hours after excercise the body can absorb twice as much carbohydrate into the bloodstream.
• At low intensities (25-50% VO2 max), carbs during exercise reduce fat oxidation compared to fasted trainees.
• At moderate intensities (63-68% VO2 max) carbs during exercise may reduce fat oxidation in untrained subjects, but do not reduce fat oxidation in trained subjects for at least the first 80-120 minutes of exercise.
• Carbohydrate during exercise spares liver glycogen, which is among the most critical factors for anticatabolism during hypocaloric & other conditions of metabolic stress. This protective hepatic effect is absent in fasted cardio.
• At the established intensity level of peak fat oxidation (~63% VO2 max), carbohydrate increases performance without any suppression of fat oxidation in trained subjects.
References
Melanson EL, et al. Resistance and aerobic exercise have similar effects on 24-h nutrient oxidation.. Med Sci Sports Exerc. 2002 Nov;34(11):1793-800.
Ahlborg, G., and P. Felig. Influence of glucose ingestion on fuel-hormone response during prolonged exercise. J. Appl. Physiol. 1976;41:683-688.
De Glisezinski I, et al. Effect of carbohydrate ingestion on adipose tissue lipolysis during long-lasting exercise in trained men. J Appl Physiol. 1998 May;84(5):1627-32.
Coyle EF, et al. Fatty acid oxidation is directly regulated by carbohydrate metabolism during exercise. Am J Physiol. 1997 Aug;273(2 Pt 1):E268-75.
Civitarese AE, et al. Glucose ingestion during exercise blunts exercise-induced gene expression of skeletal muscle fat oxidative genes. Am J Physiol Endocrinol Metab. 2005 Dec;289(6):E1023-9.
Wallis GA, et al. Metabolic response to carbohydrate ingestion during exercise in males and females. Am J Physiol Endocrinol Metab. 2006 Apr;290(4):E708-15.
Coyle, et al. Muscle glycogen utilization during prolonged strenuous exercise when fed carbohydrate. J. Appl. Physiol. 1986;6:165-172.
Coyle, et al.. Carbohydrates during prolonged strenuous exercise can delay fatigue. J. Appl. Physiol. 59: 429-433, 1983.
Horowitz JF, et al. Substrate metabolism when subjects are fed carbohydrate during exercise. Am J Physiol. 1999 May;276(5 Pt 1):E828-35.
Febbraio MA, et al. Effects of carbohydrate ingestion before and during exercise on glucose kinetics and exercise performance. J Appl Physiol. 2000 Dec;89(6):2220-6.
If you can't explain it simply, then you don't understand it well enough.