Sugar Coating Your Performance

gas analyzer testing athletes

Not very practical

Welcome to Part V of the Sock Doc Essential Guide to Carbohydrates. Part IV was way back in June in which I discussed the hot topic of ketosis in athletes. Parts I-III discussed the many roles, both positive and negative, of carbohydrates in an athlete’s diet. The gist of the story is that you want to be using fat for fuel as much as possible, especially if you’re an endurance athlete, but even more so for overall good health. Carbs aren’t evil, they’re just overeaten by most athletes and their bodies rely too heavily on them as an energy source.

So how do you know if you’re using primarily fat or sugar as a fuel source during the day while you’re working, sleeping, or training? That’s very difficult to do as really the only way to be absolutely sure would be to have a gas analyzer hooked up to you all day long to measure your RER – Respiratory Exchange Ratio. This is the ratio of carbon dioxide production to oxygen consumption which correlates with the amount of fat and carbohydrates your body is using for energy. Of course, this is not practical aside from specific spot testing. However, there are symptoms you may experience if your body is running somewhat inefficiently off sugars and if you know what they are then you can work on correcting the problem.

carbs running

Is this only for while on the bike?

Are You Burning More Sugar or Fat?

So how do you know if you’re running, (literally and figuratively), more on sugar than fat? Well, if you feel like you’re having “blood sugar swings” then you most likely are not using as much fat for energy as you should be. Headaches, mood swings, concentration issues, and fatigue are often signs that your blood sugar isn’t being regulated well. I term this dysglycemia because I’ve seen enough people with these symptoms and upon measuring their blood sugar, I find it to be perfectly normal, yet they think it is low due to how poorly they feel. This is the problem with just taking a spot check blood sugar reading – it’s an absolute – it just tells you where you are at one specific time. So if your blood sugar is a normal 85 mg/dL you may feel like it’s low because perhaps it just dropped quickly from 110 mg/dL.

If you’re training consistently and not improving then you are perhaps using more sugar than fat for fuel. I’ve seen people go from very little training to many hours per week preparing for a marathon or Ironman and not lose one pound because they were burning too much sugar instead of fat. Both the diet and training are often to blame.  If you have increased your exercise and aren’t getting leaner (fat loss) then that’s another indicator that your body is using too much sugar for fuel.

Another big indicator that you’re burning too much sugar for fuel is simple – you crave sugar. If you crave sugar, especially after you eat a low carb meal, (say meat and veges), then your body is inefficiently running off too much glucose. If you crave sugar after training then you’re burning too much glucose during that period. Even though you often should eat some carbs after a long duration or high intensity workout, you should not crave them!

tinnitus athletesTinnitus and Dysglycemia

Another symptom I have personally correlated with dysglycemia is tinnitus. Tinnitus is ringing in the ears. Many people have this high (or low) pitch ringing in their ears either intermittently for perhaps 20-40 seconds at various times during the day, if not all the time. Tinnitus can be caused by a variety of health problems but it is often at least partially associated with dysglycemia in my experience. I’ve seen people improve their diet and have their tinnitus completely resolved. Actually, as I mentioned in a previous article, my health improved when I increased my high fat diet to an even higher fat diet, my tinnitus was one of those symptoms that improved. I used to get a ringing in one ear for about 10-30 seconds usually two to three times a week, sometimes more if I was pushing my body too hard. Now I only get this if I am under too much stress and not eating as well as I should be (skipping meals or eating too much sugar).

Zinc is the most common nutrient I see a need for with my patients who have dysglycemia issues and who also are experiencing tinnitus. Typically 25-75mg a day can be beneficial, though some people need more, some less, and some not at all. So if you want to try some zinc then start low and of course use at your own risk.

Sleep Problems and Blood Sugar

Sleep problems are perhaps some of the earliest symptoms an athlete will experience when training too hard, or too often, or not recovering properly. Insomnia may be a problem, (can’t fall asleep or takes a very long time), or restless nights when you’re tossing n’ turning or up at various times. The most common time for a person to wake up at night due to increased stress hormones, (the cortisol and adrenalin we learned about in the previous carbohydrate articles), is between 1-3am. The reason for this is due to the acupuncture meridian system. At certain times of the day each organ is providing its highest amount of energy and the liver’s time is between 1-3am. So when the liver is dealing with blood sugar problems during the night, outside of what is normal to maintain balance, the hormonal stress affects the liver and disrupts sleep.

Furthermore, poor sleep also affects insulin sensitivity, (it makes it worse), creating a vicious cycle of poor glucose regulation affecting sleep quality affecting glucose regulation – and around and around it goes. So if you wake up between 1-3am, even a little bit before or a little bit after, suspect blood sugar problems to some extent. For women, the sex hormones, estrogen and progesterone, can also stress the liver at this time and cause a restless night.

coke athletes

Yeah! Coke makes you a better athlete!

Numb Hands and Athletes

The final symptom I’d like to mention is one that I’ve personally correlated to dysglycemia after treating many athletes over fifteen years as well as from my own experience. If your blood sugar isn’t exactly where it should be you might experience numbness in your hands either while sleeping or while exercising (especially racing).

What happens is that if you’re not getting the proper amount of sugar into your tissues, either because it’s not available or it can’t get into the tissues, (cortisol, our major stress hormone, is great at blocking this), then a muscle imbalance occurs in your upper arms between your triceps and your biceps. There is a muscle-organ relationship between the triceps and the pancreas which causes this imbalance to occur when the organ is stressed. This muscle imbalance can slightly impinge the ulnar nerve, (that’s what is commonly called the “funny bone”), resulting in numbness to various levels, particularly in the 5th (pinky) and 4th (ring) fingers. Many people think their hands go numb when the sleep because they are laying on them or the way they have bent their elbows. This is often not the case, just a coincidence. Also, if you’re running, (bent arms hopefully), and you go to extend your arms, this is where you will feel a slight “shock” in your fingers if you’re having sugar handling issues. It’s a great way to know you better get some carbs soon before the situation gets any worse especially if you’re racing.

themoreyouknow about sugarSo now that you know some common (and pretty cool!) signs and symptoms of blood sugar handling problems you can address them and become a more efficient and healthy athlete. The more you know! :)

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  1. Ben says

    So what is the fastest way to get to a healthy blood sugar level? Just go cold-turkey on sugar? I personally find it hard to completely cut out sugar, and find that even a little bit of sugar now wreaks havoc and cause weight gain etc.

  2. GeorgeH says

    I’m reading paer 4 of the Sock Doc Essential Guide to Carbohydrates. How can I getto the entire series starting with part 1?

  3. Dana says

    Hi Doc,

    I’ve just purchased a blood glucose monitor to test my postprandial blood sugar levels to determine how different foods affect me. Not sure when to test 1 or 2 hours after a meal. Any suggestions?

    • says

      A normal fasting, (that’s at least eight hours after your last intake of food), reading should be between 65-90 mg/dL. After you eat, blood glucose levels should normally increase, dependent upon what you ate. One to two hours after eating your blood sugar level should ideally be under 120 mg/dL and definitely not over 140 mg/dL which is associated with nerve damage and damage to the cells in your pancreas that produce insulin.

  4. Andrew says

    Hello Dr. Gangemi,

    I was wondering if you had any input on the type of carbs that might be best for people who are racing more than 2 hours.

    There are so many products these days from Gu to Ucan, not to mention the salts and electrolytes.

    I personally lean towards simplicity and love the idea of taking in less goop per hour.

    Thank you so much for your helpful website and your time.


    • says

      Hey Andrew – Really it’s whatever you can stomach whether that be gels or solids or fluids. I’ve been using TailWind and I like that a lot. It’s clean, tastes good (a bit salty perhaps), and digests well. I also like VFuel gels – not as sugary as the others.

  5. Matthew says

    Sock Doc,

    You are the MAN!!! For the past three weeks, I went from running maybe two days a week (recovering from Plantar Faciatis dating back to April, but your site has me getting better) to training 7 days a week with a heart monitor. I’m a middle school teacher and I get up and do a ten minute wake up routine of push ups, abs, etc. then do triathalon training at night. I bike/swim three nights a week, run three days a week, and on weekends swim and run. This last week, however, I’m starting to suffer. I am also eating way more paleo than ever before. Lastly, I quit alcohol and caffeine and drink water, club soda, and smoothies only. Every single night without fail, I wake up at 3 in the morning. I it also takes me forever to fall asleep. My questions are three…If I’m doing too much too soon, then how do I build up gradually without losing fitness? Second, if I’ve been doing strength training since New Years and running/living in Vivobarefoot shoes since October, then why is my PF still bothering me? Lastly, with that routine and diet, why haven’t I lost any weight yet?

    • says

      Hi Matt – good to hear your training has improved but I can’t answer such individualized questions without talking/consulting with you. Thanks, SD

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