Go Hard or Go Frequently?

The other night at dinner we asked our five year old the question of which came first, the chicken or the egg?

She thought about it briefly and then answered confidently saying the egg.

To which we then asked her where the egg came from?

You can imagine the puzzled look on her face and could see the wheels turning in her head. She realized she it was going to be a hard question to answer.

This can be similar to exercise with respect to whether you should do long, slow steady-state exercise or short, high intensity intervals. The last few years have seen a surge in HIIT i.e. high intensity interval training, Tabata and other intense training protocols.

However during COVID we have also seen a number of endurance feats including Everesting, round the world cycling challenges and other long distance endurance challenges.

So which one is it? Should we go hard and short or long and slow?

Well a recent Canadian study looked to answer this question. Here's what they did.

Twenty three adult, sedentary men were divided into two groups. One group did 30 second sprint intervals on the bike with two minutes rest. They repeated this four to six times and completed this workout three times per week. Over the course of the six study they completed almost one hour of cycling.

The other group rode the bike five times per week for 30-40 minutes at around 60% of their peak power. By the completion of the study this group had logged 15 hours on the bike.

Researchers wanted to know the impact these would have on fitness, body composition and blood pressure.

What they found is that those performing the endurance workouts i.e. 30-40 minutes of cycling saw greater improvements in:

• diastolic blood pressure
• abdominal fat
• postprandial lipid tolerance

Both groups showed improvements in fitness whereas with the sprint group improved endothelial function. With both groups glycemic control was better on exercise versus sedentary days.

So what does this all mean?

Don't get sucked in to the fad that exercise has to all-out, all the time. There were a number of benefits to performing longer duration cardiovascular exercise. Exercise is great for helping us metabolize carbohydrates and avoid the potential spikes and drops

A few other thoughts that come to mind:

• This study was all men. Would women show the same results?
• Endurance training demonstrated many benefits in this study. But they also did 15 times the work. Would the same benefits be seen at 10 times the work? 5 times?
• All participants were sedentary at the start. How hard were they able to push on the sprints? How would the results differ if active subjects were used? If athletes were used?
• Time is a huge constraint for many to achieve a fitness and health goal. We shouldn't discount or over-look the attractiveness of being able to complete training in 1/15th of the time.
• Ultimately the best training plan may be a combination of high-intensity short duration intervals and lower-intensity longer training sessions.

Citation

Petrick, H. L., King, T. J., Pignanelli, C., Vanderlinde, T. E., Cohen, J. N., Holloway, G. P., & Burr, J. F. (2020). Endurance and Sprint Training Improve Glycemia and VO2peak, but only Frequent Endurance Benefits Blood Pressure and Lipidemia. Medicine and Science in Sports and Exercise.