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Nutrition & Hydration 101

Updated: Jan 30, 2023

By Bob Byard, Certified USA-T Level II Triathlon Coach

Nutrition and hydration are “different animals” compared to pace, form, distance, etc. in swimming, cycling and running. The specifics of energy production to sustain speed and distance have so many variables associated that knowing exactly what and when to chew or swallow is like coaching itself – it’s part science AND art and you learn by making mistakes as your learning curve becomes “less vertical” with experience and knowledge. Let me try to explain….

You can address pace or distance for the three sports more finitely based on time, distance, power output, heart rate and other qualitative benchmarks. The same is not so easy for fluid and fuel –what, how and when we create the energy source to go faster or farther for a specific time period is not always within our control; environment, physical and mental factors are major players.

A running focus is different that pinpointing nutritional needed. You can “see” foot strike, arm swing, pace and distance – those are “real time” measurable parts of performance. You can “experience” the results of mixing carbs, protein and fasts, but not immediately as it turns into energy – there’s a delay from ingestion to transformation to energy -- AND terrain, weather, physical conditioning, etc. complicate the process. Running a 9-minute mile pace will get you one mile in 9 minute is immediately quantifiable. Eating a gel with 120 calories in 30 minutes in cold weather will not have the same timed and desired effect as if done in humid weather.

Practicing like you’re going to race is only realistic if you test and set individualized ranges for yourself in training. THEN you have to adjust where you are in that range based on what you CAN control during training or racing... THEN you hope to make more adjustments for what you can’t control. THEN you don’t know what that is until it hits you. THEN you have to make adjustments to get back into what you think is the right range. THEN you have to figure out the timing when the adjustments need to occur - and all THAT is affected by changing weather and terrain that constantly impact how energy is expended. If any of these parts of the puzzles don’t occur as planned or anticipated, the dominos begin to fall into each other. You can plan, you can adjust… and you can only wait and hope your “plan B or C” works because you usually have to – during nutrition and hydration, things “happen” and they’re not usually good….

You can never get it perfect; you can only hope to get it close. Like using a HRM, what the numbers are is historical information and not relevant to the moment – what you ingest doesn’t turn into energy immediately; lots of things impact what the result will be and when it’ll occur…

As should be evident, no two courses or training venues are identical – even the same ones change due to temp, wind, rain, time of day, humidity, etc. And other key variable impact is not only WHAT you take in, but also HOW and WHEN you intake it, and the SPEED it’s metabolized... There’s no “magic number” as to what exactly needs to be drank and eaten in training or racing.

Sorry: close only counts in nuclear missiles, hand grenades and hydration/nutrition. All you can do is have a plan – but understand “stuff happens” and you have to react and adjust. Just like the plan has to be flexible, so does your reaction. You’ve never hear me say, nor will you ever that the intake of carbs per hour is anything but “a range of”, “about”, “estimated to be”, etc.

“It all depends” for nutrition and hydration is a frustrating qualitative answer to a question without a quantitative answer – THERE IS ONLY A SUGGESTED RANGE OF NUTRITION AND HYDRATION THAT PROVIDES SOME ESTIMATE OF HOW MUCH TO TAKE IN OVER TIME. Individual metabolism, weight and body composition, physical conditioning, weather, energy/power expended, terrain, goals, etc.-- all the changes to these variables over a one hour training session or during the course of a 16-hour event can’t be totally controlled. What you ingest is “burned” differently for different reasons: your heart rate “drifts” as you exercise longer as it unsuccessfully tries to hold a constant rhythm; your pace slows or increases just by mentally interacting with competitors. Remember training with a friend vs training by yourself? You’re plan is not in stone; you react, anticipate, evaluate, adjust, react, etc. – too many parts to the puzzle – each is somewhat subjective and prohibits a specific action-reaction outcome.

There is a factual background to the science to nutrition and hydration – there is a subjective art for each athlete as to how it is best pursued…..


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