At this point, we’ve reviewed the basic categories of exercise, including aerobic exercise, High-intensity Interval Training (HIIT), walking, and Strength Training (ST), so let’s go over an optimal weekly exercise plan for extending longevity and a healthy lifespan.
First, let’s see how the various categories of exercise compare for extending life, using an example case of a 40-year-old man:
Hmm. Well, it looks like roughly a tie at ten extra years of life between walking and HIIT and a distant runner-up for Strength Training at a little under two additional years. Of course, other factors might give you a preference for one physical activity category over another. Let’s go into the details of each of them to see what the optimal longevity workout would be.
By walking, I’m talking about the low-intensity physical activities you could do during your day. Walking is the most common example, and other examples include household chores, like cleaning, cooking, and gardening, or casual activities like a leisurely bike ride or playing in the water.
We already know that walking is good for reducing blood pressure, preventing strokes, and losing weight, but let’s quantify how it helps longevity specifically. The benefits of walking are most significant for the first couple of thousands of steps, with diminishing benefits the longer you walk. Here’s the ten-year benefit for walking broken down into the number of steps:
As you can see, about 70% of the ten-year longevity benefit is from the first 8,000 steps, with the additional 4,000 steps only giving an additional three years of lifespan. Although the chart only shows the longevity benefit of walking up to 12,000 steps per day, studies show that the apparent benefit from walking continues to increase at a low rate well beyond 12,000 steps. This is because Low-intensity Physical Activities are gentle enough that they don’t wear out the body, and continuing them throughout your day provides an increased lifespan.
While the easiest from an effort perspective, walking is by far the most time-consuming of the physical activity categories. Walking 12,000 steps a day will take about 2-hours of time, which may be a challenge to incorporate into a daily schedule.
High-intensity Interval Training
HIIT is the critical component of aerobic fitness. We’ve seen before that HIIT improves lung and heart capacity and increases capillary density and mitochondria. By doing active rest intervals, such as jogging in between all-out runs, HIIT can provide the benefits associated with standard aerobic exercise plus the benefits from the high-intensity effort.
Here’s the breakdown of the longevity benefits of continuous aerobic exercise and additional help from HIIT:
Over 75% of the longevity benefit from aerobic and HIIT activity is from the HIIT portion. Since they both can be trained effectively in the same workout, they provide a high return for doing HIIT for half an hour a week. The trade-off is that it’s important to do it every week since just a few weeks off can cause a significant loss of fitness.
In addition to extending life, ST helps lower diabetes risk, reduces blood pressure, and builds strong bones, as well as building muscle and strength. From a longevity perspective, ST doesn’t provide as much extension of life as HIIT but is comparable with just aerobic exercise and takes much less time than walking.
Best Exercise for Time Spent
While all categories of physical activity provide benefits, this blog is about quantification and prioritization. Let’s look at which physical activity gives the most life bonus time for the least activity time.
At a minimum, I would want at least twice as much time back in extra life as I put into physical activity, and as you can see from the chart, all the physical activities meet that standard. HIIT, which includes the benefits of aerobic exercise, is the faraway winner. If continued, 20 minutes of HIIT per week can add over ten years of life, which works out to almost two days of additional life per 20-minute weekly workout. Unfortunately, the benefit from HIIT seems capped, so doing more than one workout per week doesn’t add extra longevity, although other benefits may increase.
Even aerobics without HIIT intervals returns almost fifteen hours of extended life per 20-minute workout.
Next up is Strength Training, with a return of ten times as much time as put in, assuming you keep your total weekly workout time to about fifty minutes. Well worth the effort, but if longevity is your primary goal, be careful not to get carried away. After an hour of total weekly time, the longevity benefits begin to reduce, and if you’re spending over two and a half hours a week on ST, then you’ll live no longer than if you had never started.
Last is walking; although it has the lowest return factor, it has the benefit of being unlimited in benefit. Increasing daily steps to 6,000 over the typical 4-5,000 steps a sedentary person does gives a time return of about eight times the time spent walking. Additional steps past 6,000 steps add more life, but less than the first 6,000. At 12,000 steps, the increased life span is a little over double the time spent, and it seems this benefit continues past 12,000 steps, as well.
For any physical activity, it’s best to start slowly. When the target is a long life, assume you’ll have time to work into the exercises gradually you feel give the most benefit. For example, if you want to do HIIT, start with a jog or some other aerobic exercise for several weeks before beginning with the high-intensity portion to triple the gains. Likewise, starting easy and building for ST or walking is an excellent way to establish healthy habits for long life.