The 1977 Exercise Protocol that Increased Fitness More than Any Other

A depiction of an old school exercise physiology laboratory (Image Generated by DALLE-2)

Key Points:

• This 1977 study took 8 average, previously untrained individuals, subjected them to an extremely challenging 10-week exercise protocol (40 minutes per day, 6 days per week), and increased their maximal aerobic capacity (VO2max) by 44%
• Maximizing exercise adaptations requires DIFFICULT training. In a way, “no pain, no gain” is true, and I don’t mean causing injury
• With consistent, effortful training, it is possible for even average individuals to reach fitness levels of high-level athletes

Pushing the limits of human capacity has long been interesting to our society, dating back to the first recorded Olympic Games in the Greek city-state of Elis in 776 BC (and likely at least hundreds if not thousands of years before then). Numerous training protocols and regimes that have made attempts to optimize performance and maximize exercise adaptations have been developed. What is also clear based on the average 100meter or marathon records throughout history is that humans are getting faster and faster. These improvements in record times are largely attributed to improvements in technology, increases in participation (and thus ability for athletes with a wider range of talents being able to apply their skills to a sport), dietary optimizations, and also training programs.

This article will discuss the final piece, training programs, based off of a 1977 research study (https://doi.org/10.1152/jappl.1977.42.3.372) in the Journal of Applied Physiology from the legendary laboratory of J.O. Holloszy. The goal of their study was to apply an exercise program designed to produce the fastest, most impressive improvements in cardiovascular fitness to date. In order to do this, they recognized this training protocol needed to be HARD. There are likely molecular mechanisms that require significant increases in energy demand at the cellular and mitochondrial level (possibly related to AMP/ATP ratios, activation of AMP Kinase, etc.) to drive this level of adaptation, but I won’t discuss those here (future articles will!). What I will say is that this protocol drove the 8 lucky subjects to their limits 6 days a week for 10 weeks.

The protocol was this:

— 6 days per week for 10 weeks: 3 days per week biking on a stationary bike, 3 days running on a track

— Now the cycling part was intense: Six, 5-minute long HARD intervals, such that they achieved their VO2max during each interval. Between those 5 minute periods, they cycled at a resistance that elicited 50–60% of their VO2max. As their fitness increased each session, so did the intensity, as they re-measured the subjects VO2max every week.

— To ensure that subjects were working as hard as they could, if they could maintain the biking resistance for the entire 5 minutes during a session, the physiologists would increase the resistance (!)

— The running part consisted of running as far as you possibly could in 40 minutes (!). Week 1 sessions were 30 minutes long, Week 2 sessions were 35 minutes long, and then they graduated to 40 minutes for the remainder of the study

Now the results speak for themselves (Figures reproduced):

Now what you see is that body weight was not particularly impacted! This is a very important but subtle point. Energy balance still applies. Though they absolutely were burning way more calories than they were before this routine, it is almost certain they ate more calories due to increased hunger throughout these ten weeks.

I reproduced this figure with the individual data points, so that you can see in the individual variability. There was an average increase in fitness every single week. Week 7–8 looks close (they only increased by 0.01 Liters of oxygen per minute), and I wonder if the physiologists thought they might’ve reached a plateau. Try clicking around the interactive graph to better observe the trend.

They also did an endurance test prior to the study that required them to maintain a cycling cadence of 60 RPM at a resistance level that elicited exhaustion in 2–5 minutes. This resistance level was maintained for the duration of the study, and they were retested weekly to see how long they could hold on. Again, we see that every week they were able to cycle for longer and longer. (I don’t know when they fit this in to the study protocol). Unfortunately the weekly individual values were not available, so I approximated the values from the line graph!

This study was (and remains) unique for several reasons.

By monitoring the increase in fitness every single week, the protocol required participants to work as hard as they possibly could every single session, rather than working at a fixed percentage of their pre-exercise VO2max. It has been classically shown that when you do work for say 10 weeks at 70% of your VO2max, you are able to complete the endurance exercise session at a lower heart rate, rely more on fatty acid oxidation than carbohydrate oxidation, and perceive the session as easier. This study did not allow for the subjects to feel that relative easiness as each session was just as difficult as the other. The endurance test, though, remained at a fixed percentage of their pre-study maximal endurance, and we see that they were able to go for much longer at the same cycling resistance.

In addition, this is one of the few studies (even today) that pushed subjects to failure every single session. I imagine this would be subject to much criticism today if implemented into athlete training programs. However there is some interesting work (I know David Bishop’s lab has performed some of this — See this great review, plug this DOI# into google to find it: DOI: 10.1007/s40279–018–0936-y –in addition to some others) that demonstrates high intensity exercise (like reaching near 100% of VO2max) is required for maximal mitochondrial energy production capacity, though high volume training (that is endurance exercise for 1+ hours) drives adaptation to mitochondrial volume. Perhaps the next 10 weeks of this protocol would then incorporate more long duration, lower intensity sessions to maximize mitochondrial content in order to take advantage of this knowledge.

I find it fascinating that this protocol required only 40 minutes per day, and 240 minutes per week. Now, every session was vigorous, but as far as time efficiency goes, this is very straightforward and even manageable for relatively busy individuals.

The bottom line is, you need to PUSH to realize gains. I have been asked many times if walking daily is one of the best things one can do for their health. My opinions are varied. If your goal is to offset/delay aging and functional decline, walking will help maintain your bottom line. If you really want to protect against chronic disease and maximize the benefits of an exercise session, walking will not raise your top line. To be clear, I never advice AGAINST walking! Definitely do it, and something is ALWAYS better than nothing. This paper provides evidence that if you push the limits of your top line fitness on a regular basis, you will reach a new set point.

Now, the interesting study would be then, after these 10 weeks of brutality, what is the minimum amount of exercise needed to maintain that VO2max…

Anyone wanna give that a try?