Last weekend I experienced my first bonk in about 15 years.  It was a completely amateur move.  We were on a long weekend ride.  Earlier in the ride a couple of my riding companions were starting to suffer.  In my generosity I gave a way much of my food and gels.  I was a bit too confident in my endurance.  About 15 miles from home I felt the bonk coming on. I was regretting giving up my on-board fuel.  My legs were heavy and they were wanting to slow down.  Five miles from home I wanted to get off of my bike and take a nap in the ditch.  When I finally made it home I barely had the energy to make a snack.

When I was younger and training for racing I thought of the Bonk as a training tool.  A couple of good bonks each year was great for endurance training.  I was training my body to burn fats as a fuel source and a good bonk was me testing the limits of my endurance.

That all changed in college when I took an exercise physiology class.  One day my professor said "Fats burn in a carbohydrate fire!" I asked him what he meant by that.  His answer was a revelation and changed the way that I approached endurance training.  What he told me was that while fats provide a tremendous amount of energy, carbohydrates or the sugars in your blood and muscles run the metabolic machinery that turns fats into energy.  So when I was bonking it was not because I managed to deplete my body of fats, rather I had depleted my stored carbohydrates and I could no longer use my stored fats to keep the legs turning.  This was not doing much for my endurance training.

The key to making sure that you are getting the most out of your endurance training is regularly taking on fuels whether in the form of energy bars, gels or energy drinks.  There are plenty of great products available and many that we carry here at M.B.W.  There is plenty of hype and endorsements by Pro athletes.  The product that is right for you is the one that tastes good and one that does not make you feel bad when you consume it during physical activity.  The product that tastes good is the product that you are more likely to consume on your next ride.