I started out in the beginning of my long run training with trying sports drinks or electrolyte tablets in my hydration bladders. In addition to the sugary drinks, I was using energy gels every 45 minutes, chewable blocks every 20 minutes, and even tried solid food bars. This was way too much and left me feeling bloated by miles 14-16. I felt thirsty, but also felt so full!
On the other end of the spectrum, I tried going with pure water and energy gels with limited water intake. I tried this last system, because of the research of Dr. Tim Noakes (2012).
Noakes (2012) asserts many contradictory statements to conventional wisdom about endurance exercise. He states that the heavy commercialization of the sports industry (e.g. Gatorade, Nike, etc.) has had an impact on peoples' perceptions of appropriate training and exercising techniques (p. xvi). Additionally, Noakes cites many research projects studying the effects of sodium deficiency on muscle cramping and heat exhaustion (e.g. Miller, Mack, et al., 2010b; Ladell, Waterlow, et al., 1944ab; etc.) (p. 120-127). Noakes highlights how these studies contradict early assumptions and that muscle cramping may in fact be caused by the central nervous system and not sodium deficiency. Also, Noakes discusses the limitations to early testing methodologies for sodium levels in humans.
From this reading, I gleaned many things. One, we are overhydrated conformists chomping at the bit to improve our performance through tricks and cheats rather than dedicated training. Two, our brains have a huge impact on our performance and mood throughout prolonged exercising. Knowing these two key pieces of information, I have tried to experiment with my training habits; which, brings me back to why I tried to simplify my nutrition and hydration during exercise. I can tell you anecdotally a few truths from my experiences thus far.
Water alone does not work for me. I felt wretched and full after long runs. I was bloated, unable to urinate, and felt symptoms of hyponatremia while still feeling a sense of extreme thirst. This was even after trying to modify the quantity of what I drank (i.e. only drink when very parched as Noakes suggested in this podcast about his book and research). Temps during these runs probably reached a peak of 95F with anywhere from 20-50% humidity. So, if sugary drinks and pure water were not for me, then there had to be a happy medium. Enter, Success Caps (S! Caps) and a dedicated running vest.
Now that I am serious enough about distance running, I asked for a running vest for my birthday. I wanted a vest that could hold a reservoir in the back, smaller bottles up front, and all of my energy gels and related trash. I settled on the Vapor Cloud vest by Nathan. The vest has had a tremendous impact on my runs.
I now run with clean water in my hydration bladder, and two smaller bottles with sports drink in the smaller pockets up front. I have Cytomax pre-mixed in the smaller bottles and Nuun Tablets for diversity later on in the run. Additionally, I now take two S!Caps every hour with plenty of water. I have found that this hydration combination helps me feel comfortable throughout the entire run and meets many of my electrolyte needs. Remember, before this combination, I would feel lethargic and bloated, but now, I feel energized and hydrated throughout; so, I believe there is anecdotal evidence to suggest the importance of sodium intake (I'll come back to this shortly).
As far as energy gels, there are many on the market right now. If you are looking for a more in-depth article about comparisons of energy gels, I would check out a late 2008 article on irunfar.com found here. However, my personal preference so far, is the Gu name brand. Their flavor selection, ingredients and overall taste help keep me sustained on my runs without that sloshing stomach feel. I take one gel every 45 minutes unless I'm toast at the end and then I'll add in another one or two gels. I noticed the Gu Roctane tastes worse, but may have added energy benefits down the road.
If you are looking for solid food suggestions, I would look no further than peanut butter and jelly rolled up in a tortilla of your choice. I recently tried this on my last long run and it was fantastic for many reasons. Namely, it is easy to make and eat with minimal trash and it has two crucial ingredients with powerful chemistry (i.e. sugar from the jelly for an immediate burst, and energy from the peanut butter for long-term effects). I wish I could take credit from this simple solution, but someone who had recently ran a marathon told me about this one.
In conclusion of this whole section, I'd like to get back to the importance of sodium intake and the power of influence from our brains. If Noakes and other researchers are suggesting that sodium intake takes longer to enter the digestive system than the immediate effects we feel, then why do we feel better right away? I believe this is two-fold: 1) the power of suggestion (i.e. placebo effect); and, 2) we know that the enzymes in our saliva is the first step to digestion and that sugar can immediately enter the bloodstream here.
We all know the power of suggestion is big in many areas. Why would exercising for an inordinate amount of time be any different? I once read on another running blog to know the difference between soreness and pain. You can run through soreness, your body is more than capable of doing that. Pain is a trickier to distinguish your body's ability to keep going.
If sugar and other electrolytes can enter the bloodstream here, then I believe our brains feed on that immediate source while the normal course of digestion takes place. Furthermore, I believe a well-fed brain helps maintain homeostasis and normally function systems. This not only leads to better temperature regulation but also prevents your brain from sending pain signals to your muscles that might force you to stop exercising.
Again, these last sentiments are highly anecdotal with no sources to cite or empirical evidence to back up my assertions. These are merely my observations and feelings from my experiences during these long events. I would love for somebody to point me to scholarly research that points to the middle of the spectrum - a source that takes all of the data and combines it into readable terms.
W, L. (1949). Heat cramps. (2), 836-839.
Miller K., Mack G., Knight K., et al. Three percent hypohydration does not affect threshold frequency of electrically induced cramps. Med Sci. Sports Exerc. 2010a; 42, 2056-2063
Noakes, MD, DSc, T. (2012). Waterlogged: The serious problem of overhydration in endurance sports. Champaign: Human Kinetics.