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Visa fullständig version : Ingen minskad aerob kapacitet vid utbyte av kolhydrat mot protein i sportdryck


King Grub
2009-11-20, 10:28
The purpose of the present study was to investigate the aerobic capacity characteristics of an isocaloric carbohydrate (CHO) plus protein (PRO) drink and a low-calorie CHO plus PRO drink against a traditional 6% CHO sports beverage. Twelve male and female trained cyclists exercised on 4 separate occasions at intensities that varied between 55 and 75% &OV0312;o2max for 2.5 hours and then at 80% &OV0312;o2max until fatigued. Supplements (255.4 +/- 9.1 mL) were provided every 20 minutes and consisted of a 4.5% carbohydrate plus 1.15% protein complex (CHO/PRO H), a 3% carbohydrate plus 0.75% protein complex (CHO/PRO L), a 6% carbohydrate supplement (CHO), or a placebo (PLA). Time to fatigue at 80% &OV0312;o2max was significantly longer (p < 0.05) during the CHO (26.9 +/- 6.1 minutes, mean +/- SE), the CHO/PRO H (30.5 +/- 5.9 minutes), and the CHO/PRO L (28.9 +/- 6.5 minutes) trials compared with the PLA trial (14.7 +/- 3.4 minutes), with no significant differences among the CHO, CHO/PRO H, and CHO/PRO L treatments. In general, blood glucose, plasma insulin, and carbohydrate oxidation were elevated above PLA during the CHO, CHO/PRO H, and CHO/PRO L trials, whereas plasma free fatty acids, rating of perceived exertion, and fat oxidation values were lower during the CHO, CHO/PRO H, and CHO/PRO L trials compared with the PLA trial. Only minor differences in blood parameters occurred among the CHO, CHO/PRO H, and CHO/PRO L treatments. In summary, partially substituting PRO for CHO in a sports drink did not enhance aerobic capacity, but substitution was able to occur without loss of efficacy. Thus, adding PRO to a low-calorie CHO sports drink may be an effective strategy to enhance aerobic capacity while limiting carbohydrate and caloric consumption.

J Strength Cond Res. 2009 Nov 17. Added Protein Maintains Efficacy of a Low-Carbohydrate Sports Drink.

plattenbullen
2009-11-20, 11:30
Tack för den!
Jag undrade precis hur jag kunde dra ner mitt kolhydrat intag och öka mitt proteinintag generellt! Jag har alltid laddat mer kolhydrater innan konditionsträning, men nu kan jag pumpa i mej proteiner istället! HEHE :)

Los
2009-11-20, 15:02
Protein under långa tränings/tävlingspass förbättrar återhämtningen (dock inte glykogeninlagring) så helt meningslöst är det inte.

King Grub
2009-11-20, 15:07
Man har även sett förbättrad glykogeninlagring med protein tillsammans med kolhydraterna.

http://jap.physiology.org/cgi/content/full/93/4/1337

http://grande.nal.usda.gov/ibids/index.php?mode2=detail&origin=ibids_references&therow=746224

Los
2009-11-20, 15:16
Man har även sett förbättrad glykogeninlagring med protein tillsammans med kolhydraterna.
Hmm, hade för mig jag nyligen läste en artikel (postat på Kollo) om att protein inte påverkade glykogeninlagringen.. Men om det gör det så är det ju dubbelbra :thumbup:

Guddi
2009-11-20, 19:36
Hmm, hade för mig jag nyligen läste en artikel (postat på Kollo) om att protein inte påverkade glykogeninlagringen.. Men om det gör det så är det ju dubbelbra :thumbup:Blandade resultat, troligen beroende på mängderna kolhydrater.