How I came to neglect nutrition

Until recently, I’ve focused almost exclusively on the physical aspects of my training. Yes, I do eat, sleep and go through mental highs and lows like everyone else. However, most of my focus has been on getting the workouts done day after day after day. I suppose that I have to tackle one habit and fill knowledge gaps in reasonable increments. 

When I started this journey in late January (Initially, my goal was an Olympic triathlon, not a full Ironman) I didn’t know how to run properly, I had only ridden a road bike two or three times and I thought that I knew how to swim properly.  Johnny, my trainer, very quickly let me know that I was truly at the beginning. Meaning, not only was I not in “shape” for a triathlon, I didn’t have proper form for any of the disciplines. I needed to learn the proper techniques and form to run, bike and swim properly. All of these skills were in addition to developing the strength and stamina that would allow me to complete an endurance race (an Olympic length, half or full Ironman triathlon). 

Well, today I learned first-hand that physical preparation is insufficient for race readiness. Nutrition is just as important as physical exercise. Within this sport, nutrition is referred to as the fourth discipline (swimming, cycling and running being the first, second and third disciplines). In January, in addition to starting my training regimens, I was in the middle of learning to eat via intermittent-fasting. Through fasting, I developed a new relationship with eating & food while losing weight and feeling very good. One of the components, of course, is reducing my daily caloric intake. Rather than being restrictive, I was simply eating less and choosing healthier foods. This kept me satiated while I consumed fewer calories throughout the day. 

I knew that when my daily training became more intense, I would need to increase my caloric intake. The success that I’d achieved through the intermittent fasting was a strong deterrent to any changes. I simply wasn’t confident that I would be able to avoid falling back into my old eating habits. I still loved potato chips I and fried foods. Sweets before bed are just delicious.  As a result, I have been under-fueling.

For the most part, I’d been getting by fairly well.  But, with increasing frequency, I’d begun to notice the greater feelings of fatigue and hunger after my daily workouts. I focused on choosing more calorie-dense foods as well as (mostly) avoiding the salty-fatty snacks that I enjoy. Also, I had gotten lazy about tracking meals, so I’m sure that my nutrition became inconsistent. In spite of these challenges, my body continued reshaping while my endurance was increasing so I half-assed focusing on my nutrition. I am hard-headed, excuses can be found everywhere. 

Cycling performance test

Today, I did an 8-week bike assessment. We do them to gauge physical and metabolic progress. These results help to guide the subsequent training plans. It’s a reality check too. If I’m not putting in the work, the assessment shows a lack of progress.  In this case, the bike is fastened to a stationary trainer.  The trainer had a resistance setting that Johnny increases at pre-determined times during the test. Before I begin riding, he takes a baseline pulse and blood lactate reading. My resting heart rate is 62 and my lactate is 0.5 mmol/L. Both are good. The resting heart rate will continue to decline as my physical condition improves. Johnnys gets to the high 30s – low 40s when he’s in race shape.

A little bit about metabolic measurements and energy use

Athletes use several metabolic measurements to track the effectiveness of their training. A few that I’ve learned to use are; VO2 max, Heart rate (pulse), Blood-lactate, lactate threshold, the onset of blood lactate/ lactate turning point (OBLT/LTP) and power (watts).

Heart rate is commonly measured to determine how hard your heart is working at various intensities of activity.  Lactate is a metabolite that athletes use to determine proper training intensities. It’s a product of glucose (anaerobic) metabolism. So, if you are exercising at lower intensities your body will primarily use fat stores for energy (aerobic metabolism) which won’t increase blood lactate levels. Those levels increase once the body has switched to anaerobic metabolism (your heart rate is much higher and you are breathing hard). As your muscles use glucose, lactate is produced. If it accumulates faster than it is cleared you will experience muscle fatigue (jelly legs or burning muscles).  The goal is to train your body to work harder without producing or accumulating lactate. 

The cycling test was great…then it wasn’t.

My resting lactate was 0.5 millimolar which is very good. Just as before, I ride for 3 min then he increases the resistance. My job is to maintain my cadence (70 RPM) and ride until I reach my maximum effort. During the test, my heart rate is continually monitored and my blood is sampled at the end of each 3 min segment. The current objective of my training is to build my base; increase my ability to work harder without switching into anaerobic energy production. 

I felt great during the first 3 segments of the diagnostic test. I started having trouble maintaining my cadence during the 4th segment and barely made it through the 5th. During the last minute of the 5th segment, I was unable to get up to 70 RPM. I hit a wall, no more energy. 

I felt like someone literally sucked all the juice out of my body. I wanted to just stop pedaling. Johnny was pushing me to finish the segment; he even modeled the proper breathing rate.  I didn’t know what was happening, I felt great just 5 minutes prior. After taking the blood sample (a finger prick) he asked if I was good to go for the next segment…..No was all I could muster. 

The assessment was over.

Then he said, if I had been in a race, about 30 minutes into it I would have fallen apart. I was completely depleted of my glycogen stores. Since I was working hard enough to switch my metabolism to anaerobic energy generation, glycogen stores are critical. Once those are gone, the body struggles to provide fule to keep the muscles firing. 

A lesson from the master

Johnny told me that he knew that my sudden crashing was due to inadequate nutrition and not exhaustion because of the way I recovered afterward. If I had raced to my maximum effort, then after stopping I would have been completely out of breath for a full two to three minutes. That didn’t occur. Instead, I was out of breath then very quickly after stopping I regained my breath (less than 1 minute). 

We then spent some time discussing proper fueling and how to better prep my body for these types of intense sessions. Basically, I should continue to lean-out by reducing the intake of fats and increase my intake of complex carbs to replenish my glycogen stores. 

As we reviewed my results, I made two important insights. See the image below.

  1. I have made good power and efficiency gains (lactate takes longer to accumulate). Also, my heart rate is lower although the power produced is higher. 
  2. I have consistently been unable to push into the higher intensity zones (I never get to 6 mmol/l ). This signals an energy reserve problem. I need to improve my diet so that I have adequate reserves for prolonged high-intensity activity.

Overall, I was disappointed in my performance while feeling happy about the progress that I’m making in building my base…aka endurance. Now is the time for me to begin more serious consideration of my diet. I expect the training sessions to get longer and increase in intensity.