When people start a cardiovascular fitness program they are sometimes under the illusion that they will get fit quick and once they have improved their CV fitness level they can stop and go back their previous sedentary habits. They don’t realise that it takes time and commitment to get CV fit and then a longer time to maintain their improved fitness level.
The sad reality is that once they stop training, their CV fitness can be lost at a faster rate than it took to gain.
Cardiovascular fitness causes major changes in the heart, blood, blood vessels, organs and the skeletal muscle. The greater the changes in cardiovascular fitness the fitter we become. In other words, our maximum aerobic fitness (VO2max) will increase proportionally to these major changes.
The interesting point is that the fitter people who have a higher VO2 max (>55 ml.kg.min-1) and have been training for some years have more to lose than those who are regarded as moderately fit (<55 ml.kg.min-1).
So what happens to our fitter friends if they decided to go on a four weeks holiday and choose to relax, eat and drink and generally laze around without any exercise?
After three weeks of sun, surf and lazing around they can potentially lose 7-11% of their maximum aerobic fitness (VO2max). This is a rapid decline in a relatively short period of time. After three weeks, the decline will not be as rapid but will still decline eventually slowing down.
In our moderately trained group the four weeks holiday will only cause a small decline in VO2max.
Apparently the difference between the two groups is due to the greater heart action in the trained group than the moderately trained group.
The first training response lost in a detraining scenario is a reduction in the heart’s ability to pump blood per beat (stroke volume) ultimately causing a reduction in the amount of blood the heart can pump per minute (cardiac output). With less blood being pumped, less oxygen is carried to the muscles causing a decline in the muscle’s ability to generate aerobic energy.
In other words, the trained group are more susceptible to a loss in heart function that the moderately trained group have yet to gain. We can see this when the trained group take their basal heart rate in the morning when compared to the moderately trained group.
In a trained group the resting heart rate will start to increase after the first 7-10 days of rest while the moderately trained group will generally present with a similar resting heart rate.
The increase in resting heart rate indicates that the heart’s ability to pump out blood per beat is decreasing more rapidly in our trained friends.
After the changes in heart action other changes occur at a slower rate for both groups. For example, the blood flow to the muscle remains the same until approximately 12 weeks of rest where the moderately trained will start to lose more than the trained group. The activity of enzymes that speed up many of the chemical reactions start to decrease at about three weeks making it hard for the powerhouse of the cell to make aerobic energy.
So what are our options if we are going on holidays and want to maintain our cardiovascular fitness?
There is always the option of training normally while on holidays.
Train at least twice per week using a HITT training protocol. You can use any mode of training (bike, stepper, treadmill, etc.) for approximately 30minutes.
Pay attention to what is eaten to avoid any weight gain. Weight gain will cause a decrease in relative VO2max due the increase in body weight.
Train very hard every day for the 5–7 days before holidays without significant recovery. This places the body into an overreaching state where the recovery will take at least 7-10 days and then train with HIIT once per week for the next two weeks.
So when we are resting on the beach, our body is still be recovering from our overreached state rather than being fully recovered ready to start taking our hard earned cardiovascular responses away from us.
We should make the most of our break and look forward to regaining our lost CV fitness when we get back. The reversal of regaining our CV fitness is generally faster than when we initially started on our fitness journey.
If we are moderately trained, other than watching weight gain there is little to be concerned about as the low to moderate intensity movements of swimming, strolling, playing golf, surfing, paddling will all contribute to maintaining our CV fitness.
Sadly this might not be the case for our well-trained friends.