MWI whats your consensus on whey with water before a event (30min ie whey peak)? fast absorption rate no fat or fiber. Throw in some simple carbs.
1. What would be the affect on the stomach.
2. would it change or affect the bodies energy pathways during exercise
3. would it be beneficial or detrimental to performance
4. Is there a difference in opinion to these on short say DH events vs long events?
I don't think I have answered these questions very well (might suggest a lack of knowledge), I wonder if there's any sports dietetics in RB land?
For fluid the general guidelines are
Before competition (5-10 min before the start) 8 mL/kg body weight (400-600mL) - drinking before the event 'primes' the stomach so gastric empting is more rapid - perhaps more efficient is a better term.
During competition every 15-20 min (every 5 km) 3 mL/kg body weight (150-250mL) - this is consider more for longer duration aerobic events, if it is hot and humid, it needs to be higher yet again.
If you are not used to drinking fluid like this, a bad time to start would be before a race, practice this in training to get used to it prior to competition.
For longer duration events around 8% glucose in the fluid is perfect (pretty much what gatorade has), any more than this and gastric emptying slows down, less than this and the performance benefits are diminished. Yes, doing this will alter the bodies use of energy systems, as maintaining blood glucose levels means we avoid (diminish the % it contributes - as all energy systems work as a unified system) utilising fat as an energy source, basic meaning can make energy faster (ATP) and go at a harder pace.
I'm not entirely sure what adding in a whey would do, with or without carbs on the energy systems, from an endurance performance view, probably make performance worse? as it is not aiding blood glucose levels (as it has to be converted during a somewhat complex process).
Was thing about this over lunch, I think the guidelines for nutrition and fluid intake probably relate to DH pretty well, while DH is typically a 3-6 (?) minute race, you need to take into account the all the practice runs you do before the event, so I'd probably eat a decent brekky around 8am (AT the track), start runs from 8.30/9am onwards and have a few snacks mid morning, a light lunch then race somethere around 1pm. I always made the mistake of eating early and skipping lunch at DH races, couldn't have been good for performance.... oh well I normally crashed x3 any way.
I'll see if I can find any specific guidelines for track and field athletes - various heats would mimic practice runs in DH and those events are ongoing for hours.