Chicago Marathon Hydration and Fueling Plan

Through my 19 prior marathons I've made many mistakes with hydration and fueling. To hopefully improve at the forthcoming Chicago Marathon I put together my fueling and hydration plan with some research and thoughts: An extremely competent sports-focused Houston dietitian generally recommends that her clients consume two-grams of an easily digested form of carbohydrate per kilogram of body weight two-hours prior to the start of the marathon. For myself this translates to ~150 grams, or a 600 Calorie breakfast. Since on race day I scrupulously avoid breakfasts with large amounts of fiber, as a dietetic homage to ancient Pheidippides I will have Greek Yogurt for breakfast. I love its flavor and its addition of protein versus conventional yogurt helps to better stabilize blood sugar thereby allowing the body to better unlock its internal stores of glycogen and energy. Since the dietitian also recommends drinking plenty of sports drink the day prior to the event (so-as to be fully hydrated while increasing stores of electrolytes) I am planning to carry a bottle of Gatorade while wandering the famous Chicago Marathon Expo. Per sports dietitian Nancy Clark's recent article we can ingest at most 60 grams (i.e. 240 Calories) of carbohydrates per hour if they are solely in the form of glucose, fructose, or any other specific carbohydrate type. However, we can ingest up to 90 grams (i.e. 360 Calories) per hour if the carbohydrates are in mixed form. As a related January 2011 follow-up to this post, see this excellent Sweat Science post which provides an interesting partial answer the important question of just how much variability exists in runners' carbohydrate ingestion rate. As is noted, individual experimentation during training is key since there is no generically applicable answer, and studies point to some runners' mixed-carbohydrate ingestion rate being significantly greater than the cited 90-100 grams per hour.  Conversely, it appears that most studies evaluation of runners carbohydrate ingestion rates beyond these amounts results in them not absorbing these massive ingested amounts, thereby raising the unsettling risk of adverse stomach or digestion issues.   Tim Noakes' Lore of Running provides an excellent reference for all serious runners. Via consuming carbohydrates while running we effectively supplement the liver's and the muscle tissues' limited supplies of glucosamine, thereby eliminating or delaying the dreaded 'wall'. Both Clark and Noakes agree upon the criticality, however, of not exceeding the body's maximum hourly carbohydrate consumption capacity. In the most recent Marathon Talk (a great podcast!) interview ultra-marathon star Scott Jurek quotes the more conservative 60 grams per hour in his own fueling plan. Of particular interest, like many ultra runners - including Dean Karnazes - he adds protein and fat during his ultra-runs. Though I stick entirely with carbohydrates on my marathon and shorter distance events I have successfully added protein and fat on my three 50Ks, and similarly find that the slower pace eases the consumption of nutritionally more diverse and enjoyable solid foods. I flag this issue since slower (~5-hour plus) marathon runners may similarly benefit by following an ultra-oriented fueling plan. Jurek also cites his target warm weather hourly fluids consumption of 30 to 40 ounces, which is obviously an extremely individual determination affected by the individual, their pace, level of exertion, temperature, humidity, wind, the amount of sun, and their apparel. Determining one's sweat rate is very important and requires some discipline (as described in this article.) It is very important to know what type of fluid is being served on the runner's forthcoming marathon course and how many fluid aid stations that there will be! For example, the Chicago Marathon will provide Gatorade Endurance at twenty aid stations. Via knowing one's sweat rate, and targeting replacing the majority, but not all of one's fluid losses, the runner can set-up a hydration plan to assure that they drink adequately - but not to excess.  As a related February 2011 follow-up to this post see an interesting Sports Science post which summarizes a related study in the British Journal of Sports Medicine indicating that the fastest marathoners tend to lose the largest percentage of their initial body weight.  This runs against the general wisdom that performance degrades after one loses 2% of their body weight. Nevertheless, as I experience significant increased thirst above this level I've reflected it within my personal hydration plan.   All runners should experiment during their long training runs with various fueling and hydration strategies, so that on the day of the event they will be non-stressed and confident. Gatorade Endurance alone does not provide sufficient carbohydrates to replenish more than a small fraction of the ~102 Calories per mile which I exert while running, so I supplement with my preferred sports gel - Gu's Roctane (orange-vanilla flavor). The reasons for my loyalty are: I love the flavor, branch chain amino acids (a key building-block for the protein synthesis utilized in muscle repair), the moderate amount of caffeine (proven to enhance concentration and motivation), and without stomach upset I can consume more Roctane than other gels (in both the recent Austin and Boston Marathon I've successfully taken one Roctane at the beginning of the race then an additional one every three miles, for a total of nine!) Based on Noakes' Lore of Running (table 4.2, pp. 214), even fit and heat acclimatized individuals lose a significant amount of electrolytes through their sweat. Presuming Chicago provides typical mid-October weather, with my relatively high sweat rate of ~6 Oz. per mile this results in a large loss of sodium and potassium - even taking into account the electrolytic content of Gatorade and Roctane. Accordingly, as in past successful marathons I will additionally supplement with an easy to tolerate buffered electrolyte capsule, the Succeed S!Cap. To acknowledge the ongoing debate there's concern amongst some as to whether a runner should follow a prescribed hydration strategy such as I outline, or simply to drink to their thirst.  A recent Runner's World article outlines well both the pro's and con's, and points out the complicating variable of taking an NSAID on a marathon - which I never do (see also this link). The best article on the critical subject of hydration addresses key myths and facts, and can be found in this recent Running Times article. Finally, solely as an FYI I've listed my 2010 Chicago Marathon hydration and fueling plan.  For the above cited reasons I do NOT suggest this plan be followed by any other runner! Despite its apparent complexity it will be considerably easier for me to follow than it may initially appear. Barring unanticipated cool or hot/humid conditions (i.e. less than 40°F or more than 65°F) I intend to drink one 6 Oz. cup at every aid station, following the repeated pattern of water at the first two aid stations (taking a single S!Cap at one), then drinking Gatorade at the third aid station, while consuming one Roctane every third mile (double click the below spreadsheet graphic to see full screen):

13.  Alternatively, Chris of http://bqordie.blogspot.com/ fame recommended a far simpler fueling solution, which he's had good luck with.  Carry two, and hold one EFS Liquid Shot container by 1st Endurance (see http://www.firstendurance.com/efs-liquid-shot.html).  I haven't tried it as yet, but I'm tempted to as it's far simpler than the above approach (consume one container every nine miles, sipping along the way), and achieves nearly the same level of fueling and electrolytic levels.

Houston Marathon Race Report

Earlier today I had the distinct pleasure of running the 2010 Houston Marathon.  This was my fifth Houston and seventeenth overall marathon or beyond event, and was undoubtedly the best.

The weather was good, with clear skies and temperatures ranging from an ideal 43°F at the start, to a bit hot upper 50s peak.  A Houston record of more than 20,000 runners participated, with the full and half marathon events selling out in less than 3-days! 

This huge crowd gathered before the race with great enthusiasm and excitement, and celebrated afterwards at the George R. Brown Convention Center - a well appointed facility that ranks as the best such marathon hosting facility (perhaps explaining Houston's consistent draw of top global athletes).

As a key part of my race strategy I ran with the 3:20 pacing group, and absolutely credit that group for helping me achieve this goal - with a personal record time of 3:19:38!  As a consequence of running with the 3:20's my split times were extremely consistent, and I achieved a rare 38-second negative second half split!

ADDITIONAL CREDIT TO:

• My wonderful family, and especially my fantastic wife, for all their support.
• The excellent KenyanWay program coached by Sean Wade.
• Gu's Roctane Vanilla/Orange - which I love!  Encouraged by my recent PRs, I took one packet every four miles - or eight in total - with absolutely no stomach upset!  I believe that frequent Roctane consumption runs helps by minimizing losses of muscular glycogen, sodium and potassium - while maintaining concentration and focus.  NOTE: Especially in the critical area of nutrition a runner should try-out different strategies during long training runs well in advance of a race!
• My Newton running shoes - which I continue to swear by on race day!
• My iPod Nano and its highly motivating fast-beat rock playlist.

LESSONS LEARNED:

HYDRATION: Weighing in immediately before and after the race revealed to my huge surprise that I had lost four and one-half pounds - more than one pound beyond the maximum recommended (typically cited at two percent of body weight). I had been very thirsty and a bit light-headed in the final four miles, and in retrospect should have slowed down and drunk more through the final aid stations! Lesson learned: Trust your thirst - an excellent gauge to assuring appropriate yet not excessive hydration! Don't worry about slowing down a bit to drink sufficiently so-as to fully quench your thirst - particularly in the final miles of an event under warmer conditions.  Whatever time you might lose will be fully compensated by a safer - and a faster performance. NOTE: On the opposite side of the fluid hydration spectrum lies hyponatremia. Recognizing its potentially extreme dangers a runner should certainly not drink beyond one's thirst (evidenced by gaining weight during a run), and weighing in before and after a variety of runs builds understanding of appropriate fluid intake.  If interested in more on-topic I made a contribution to the excellent Extra Mile Podcast (http://theextramilepodcast.blogspot.com/), and my ~10-minute contribution largely on hydration lessons learned can be found on Episode 61, beginning 12-minutes into the recording.

CLOTHING: With clear, bright, humid and sunny conditions in the final miles, and the temperature rising to the upper 50's, I was sweating profusely so at aid stations poured water over my head while taking 4-Oz. of Gatorade.  While doing so brought immediate relief I should have first removed my sleeveless running shirt and run bare-chested to maximize heat losses.

MISC.:

• Geek Report - The day before the event I purchased a Garmin Forerunner 310XT which proved to work well.  It provided better accuracy than my prior Forerunner 405, and I was relieved to notice afterwards that I had used less than 25% of its battery life (as contrasted with the 405, whose battery was consistently more than 75% depleted after a marathon).
• I was very encouraged to see a factoid by runpix.com which reinforced the benefits of Kenyan Way and of the pacing group strategy, i.e. of 99 other runners surrounding me as I began the final 7.5 miles of the race only 7 crossed the finish line faster.
• I enjoyed several encouraging and humorous T-Shirts on the course, the best of which was: "This isn't sweat; my fat cells are crying!"
• Official Stats:
  Overall: 390/6287 (top 6%)
  Males: 345/3911 (top 9%)
  Division (50-54): 27/473 (top 6%)

With speedster Xabier narrowly edging me by 18-seconds we both celebrate a personal record marathon time of 3:19!