Aerobic versus Anaerobic Training

When I first started training and coaching regular individuals (as opposed to athletes) there was a well entrenched notion for weight loss. Long, slow, distance was believed to be the only way to burn excess fat. Women at the health club in the YMCA would line-up to claim a stationary bike and cycle for 1-2hours at low intensity while reading magazines, watching television and basically being very distracted from what they were there to do.... exercise!

If you can concentrate on reading while 'exercising' you are not exercising! You are passing some time, lubricating joints and mildly increasing circulation, however you are not burning excess fat. If you are lucky you might burn off the banana you had for breakfast that morning with such a workout.

Burning fat requires effort. Sucking wind as I tell clients. Get out of breath, 'puff' the effort. Sleeping people can walk! Don't just walk, pick up the pace and engage the muscles. Here's why.

Aerobic exercise simply means, 'with oxygen.' This is energy produced in the presence of adequate oxygen. Heart, nerve and brain cells can only produce energy under the aerobic conditions. Well thank goodness you don't need your brain to stationary cycle. Most cells in the body require a steady supply of oxygen and if this is not met then one can suffer a heart attack, (lack of oxygen to part of the heart), stroke (lake of oxygen to part of the brain).

Anaerobic exercise simply means, 'without oxygen.' Skeletal muscle cells can produce energy even when the cardiovascular system cannot deliver enough oxygen for the work they are doing. Anaerobic system will kick into high gear only when exercising muscles have inadequate oxygen available.

However, to maximize fat burning we need to consider the entire exercise effort before calibrating total caloric use. It is true that aerobic effort such as the long, slow distance uses a pretty good supply of stored glycogen (pasta and bread stored in the muscles) and stored body fat. But after that long, slow effort is over and you stop then the calorie burning stops! You get no post exercise effect for your efforts. That's it, the calorie burning is over! Next time you use stationary exercise equipment, input your weight and age, do the workout then have a look at how many calories you have burned. Though this will be off by some degree it gives you an idea that just moving is not going to do much of anything. Like I said earlier, you may burn off a banana and yogurt breakfast but you certainly won't use up those pancakes with maple syrup. Those calories are now on your butt or gut.

Anaerobic exercise is essential no matter what your age, fitness level, or objectives. The anaerobic system does depend on muscle glycogen for fuel and blood sugar as well. This is all true and its dependence on glycogen is why anaerobic effort got a thumbs down a decade ago. But, the anaerobic effort also:

• secretes growth hormone
• improve Max Vo2 (how efficiently your body uses oxygen)
• increases lactic acid threshold ( ultimately trains your body to tolerate more stress)(makes you FITTER. When you are fitter you burn more calories at rest!!)
  
• decreases injury risk from high repetition, over use syndromes
• up-regulates enzymes for fat metabolism
• post-exercise benefit of 1-2 hours of fat burning!!
• improves glycogen dependence (trains your body to use glycogen more efficiently)
• Once glycogen is tapped into fat is mobilized

What a bargain. Anaerobic exercise is the most efficient way to burn fat. Quick, but not easy.
Remember when you lift weights this is an Anaerobic activity. You are breathing with enough oxygen supply but on a cellular level your muscle cells are being depleted.

Next work out. Kick it up a notch. Get puffy, get out of breath, suck wind. It will pass. You will recover and be fast, fitter and leaner for your effort.

Carbohydrate Depleted Endurance Training

In today's Globe and Mail Alex Hutchison wrote an article on the merits of training / exercising 'empty.'
This is a method I have been advocating for 25years.
Essentially it calls for exercising on an empty stomach 3-6hours away from the last meal.
This is an easy route for your body to directly access fat stores for fuel. This is the lipolysis pathway. (lypolytic pathway)
With normal blood sugar levels and slightly depleted glycogen stores (this is the storage form of carbohydrates)
your body will fire up the enzymes for fat metabolism immediately. If you have fueled with sugar or gel packs the blood sugar rises, and the body will choose the sugars for fuel rather than go searching for fat for fuel. I believe that fuelling with constant supply of carbohydrates is inefficient and will cause many people to actually gain weight rather than loose fat because there is a constant demand for higher blood sugar and no burning of fat.
Like any other part of training this take will take practise to master. The more often you do not fuel for short workouts the more efficient the enzymatic pathway will become allowing you to go longer and longer durations without 'fuel.' You will still need fluids rich in electrolytes but not sugar.

As an endurance athlete I have cycled from Toronto to London Ontario (240km) on the back roads with nothing more
than 3-4litres of electrolyte drink rich in sodium, potassium, magnesium, calcium and chloride. These allow the muscles to
continue to contract with force and not become too saturated with plain water. Too much plain water leads to HYPONUTRIMIA.
Too much water not enough electrolytes and muscles slow their contractions. A drink rich in electrolytes also allows the body to access fat for fuel and not depend on carbohydrates / sugars.

The lipolytic pathway is interesting and far more detailed than outlined here. If you have further questions feel free to comment. Recreational runners would do themselves a great service to stop feeding on starch and start eating for high nutrient, normal portion sizes and let the body figure out where to get its' fuel from.

Like your mother always said, "don't swim with a full belly." Well don't exercise with a full belly either. The only competitors loading up at the pasta dinner are the recreational runners. The elites eat a balanced meal of protein, fat and some starch based on their lean body mass only.