Last Sunday, Dorrigo Urunga Bicycle Group (DUBBUG) visited the Toormina Velodrome to test the theory that short bursts of intensive cycling can have a profound effect on their health. Though, it is too early to tell, the theory is promising and was a perfect opportunity to set some new lap times.
What do mitochondria in our bodies do? They make energy.
Mitochondria are often referred to as the powerhouses of the cells. They generate the energy that our cells need to do their jobs. For example, brain cells need a lot of energy to be able to communicate with each other and also to communicate with parts of the body that may be far away, to do this substances need to be transported along the cells, which needs lots of energy. Muscle fibres also need a lot of energy to help us to move, maintain our posture and lift objects.
Mitochondria generate chemical energy, similar to the type of energy you get from a battery. The energy made by the mitochondria is in the form of a chemical called adenosine triphosphate or ATP for short. ATP is an energy currency that every cell in our body can use and it keeps us alive. It generates ATP by using oxygen, hence when we exert we try to breathe heavily to get as much oxygen as possible.
We have billions of Mitochondria in our skeletal muscles, estimated to comprise 10% body mass. Top athletes have more. How much oxygen our mitochondria can consume when we push ourselves to the limit is the gold standard measurement of aerobic fitness. It’s called ‘VO2 max’ and can be easily tested. It’s a good measure of the metabolic health of your muscles. So we know, for example, with endurance athletes that they’ll have a very high VO2 max, and people who sit on the couch, they’ll have a very low VO2 max.
Mitochondria respond by being better able to take that oxygen out of the blood into the muscles and using that to produce energy. It’s happening in literally billions of mitochondria throughout your body in fast-twitch, intermediate and slow-twitch muscle fibres.
When you do low-intensity exercise, even though it might feel like it, you’re not actually using all of your muscle. You’re only using the amount of muscle that you need to do that particular type of exercise. Whereas when we do very high-intensity exercise, especially sprinting, then you need to recruit all of your muscle fibres at once. Science believes that with the high-intensity training, you are probably replacing some of the older mitochondria with new, better-functioning mitochondria, and they think that may not be happening as much with the low-intensity exercise.
The results can be quite profound. Swapping old, faulty mitochondria for better-functioning new ones is a reward not to be underestimated. If there’s mutations in the genes that make mitochondria, this can lead to very serious diseases, e.g. strokes, seizures, muscle weakness, Alzheimer’s, obesity, type 2 diabetes and, in fact, human ageing.
In all of us, mitochondrial function gradually declines as time wears on. Although they’re very efficient at repairing themselves, eventually we can’t keep up and the cells start to drop off in energy. When they drop off in energy, they lose their resilience and the cells end up dying and we can’t replace our cells. Our muscles shrink, our skin sags, brain volume drops and soon enough we look and feel old.
The good news is that with high intensity training the body selects against the bad mitochondria and it’s almost like putting them through a biological filter. After 3 months of endurance training, people at age 86 looked like 20 to 30 year youthening of the skin under the microscope. The point is it is never too late to start.
Sprints boost mitochondrial function in a very rapid way. This is achieved via the Wingate method – just 4 x 30 sec sprints, three times a week. A total of 6 minutes per week.
Another method showing success is to pedal fast in intermittent bursts only lasting eight seconds, with 12 seconds of light exercise in between. Over the course of 20 minutes three times a week, you have actually sprinted for a total of 8 minutes.
The DUBBUG practised the Wingate method at the Velodrome and then enjoyed morning coffee at the nearby Hidden Link Café, Toormina. For the record, some DUBBUG velodrome (330m) times were:
Penny 31 secs
Bruce 31
Bello Don 28.9
Rick 32.3
Phil 29.4
Kirk 24.7
Kerrie 33.1
Steve 32
ED 25.9
Next week DUBBUG is off to Coffs Jetty – a perfect introduction cycle to those tempted to be involved in the Coffs Coast Cycle Challenge in August. Why not join us?
Dave Spears