In several large-scale studies that follow people for many years, they show that running has a dose-related effect. More running is better, though with diminishing returns.
However, the good news for couch potatoes is that the largest gains come by going from nothing to something – with the biggest health benefits being observed with just a little running per week, less than 60 minutes (an amount that would (theoretically) fit in most our schedules).
Other benefits are clear from long-term US studies. For example, in the National Walkers’ and National Runners’ health studies, Paul
Williams and Paul Thompson of the Lawrence Berkeley National Laboratory measured the health of about 16,000 walkers and 33,000 runners over six years. Compared with walkers, runners had a 38% lower
risk of high blood pressure and a 71% lower risk of type 2 diabetes.
However, when the researchers controlled for energy expenditure and weight difference between the groups the benefits from walking and running were comparable. Later on, Williams also analysed data for breast and brain cancer, and the reductions in risk of death from running or walking were, once again, similar if energy expenditure was the same.
For those of us under time pressure, even a small amount of exercise brings
significant health gains. This was the case in a massive study from 2011 that followed more than 400,000 people in Taiwan, over an average of eight years, noting their exercise habits and the number of deaths from different causes. This study suggested that just fifteen (15) minutes a day of moderate exercise, such as fast walking, was enough to reduce risk of death by 10% compared with sedentary participants. This effect could also be gained
with approximately five (5) minutes of vigorous exercise, such as running, giving a time-versus-benefit ratio between running and walking of three to one.
Locomotion
| Walking | Running | |
|---|---|---|
| Touching the Ground | At least one foot is always touching the ground | Both feet are airborne, followed by one foot making contact with the ground |
| Technique | Efficient | Less Efficient |
| Motion | Body acts like an inverted pendulum during each foot’s contact | More like the compression of a spring than a pendulum’s swing |
| Force | Normal | Experiences forces that are more than double those encountered when standing |
Time Spent Exercising vs. Additional Years & Other Benefits
Duck-chul Lee (Iowa State University) and colleagues sought data to find out if the time spent exercising was worth the benefits (i.e. is the time spent running to gain extra years of life are equal to the number of years gained).
- They calculate that between the ages of 44 and 80, someone who runs two (2) hours per week will spend a total of 0.43 years running.
- This would still provide an average ‘bonus’ of 2.8 additional years of life on top of the time spent running.
- In other words, one (1) hour of running typically adds an extra seven (7) hours to lifespan.
We have yet to discern whether progressively more running provides further mortality benefits, but we can state with certainty that running certainly provides cost-effective longevity benefits.
Time-Constrained Exercisers
- Time Rich: The gains of walking are comparable to those of a jog, so long as you are moving at a moderate pace.
- Time Poor: Running is the best way to get a dose of exercise.
The fact that running confers similar benefits as walking but in half the time is one major reason that running is attractive for health.
It is important to note that even a small amount of exercise boosts health, but this effect tapers off with increasing time spent exercising.
Higher vs. Lower Intensity
There may be additional benefits of running, particularly for cardiovascular health, related to the higher intensity of running.
However, intensity is relative to individual fitness levels, and a brisk walk will provide numerous health benefits for people like beginners and older adults.
The Risks of Running
Running Will Wear Out My Joints
Wear and tear, and the risk of injury, could outweigh all the benefits of running. But, does running wear out our joints like some believe?
A study by Alister Hart, Laura Maria Horga, and colleagues which recruited 82 runners taking part in the London marathon, all of whom were over 40 and had never run this distance before suggests not.
Using MRI, the runners’ knees were scanned in detail six months before the race and again a few weeks after. The scans revealed that the knee’s main weight-bearing compartments – the parts most likely to develop arthritis in the long term – had become stronger as a result of the marathon training. However, the kneecap part of the joint did show damage, but follow-up scans revealed that this had reversed six months later, when the participants had reverted to less intense running regimes. This research suggests that distance running can have long-term benefits for your knees.
The same team also conducted a study on hips, which found that 560 kilometres of a marathon training programme, ending in the race, did not cause pre-arthritic changes in the hip joint. The findings suggested that the high impact forces during marathon running were well tolerated by the hip joint.
Other research from data based on the National Walkers’ and National Runners’ health studies looking at osteoarthritis (which is caused by the breakdown of bones or cartilage in joints) suggests that doing more running or walking actually reduced the risk of osteoarthritis and the need for hip replacements. It did not seem to matter if the participants walked briskly or ran slowly.
Essentially, the idea that running wears the body out is a myth. In fact, the reverse is true – Running helps activate all kinds of repair and maintenance mechanisms.
However, that said, you can overdo it.
A 2017 meta-analysis, including more than 125,000 people, found that 3.5% of recreational runners had osteoarthritis in the hip or knee compared with 10% of sedentary non-runners. However, 13% of elite runners who had taken part in international competitions had such osteoarthritis.
From this we can state that for recreational runners, at least, it seems there is a range at which running protects against osteoarthritis, and a point at which it does not.
What about Strains and Sprains?
When it comes to injuries such as sprains, walking beats running.
For example, a study of the exercise habits of more than 14,000 Spanish graduates found walking resulted in 40% fewer injuries than running (for equal energy expended).
The injury rate of running was less than that of football, sailing and martial arts, and similar to that of skiing and tennis.
When running, the risk of injury depends on a number of factors such as:
- How long you have been running.
- Novice runners are more likely to get injured than experienced runners.
- Approximately 18 injuries per 1,000 hours of exercise or about one injury for every 540 km (double that of experienced runners).
- Previous injury.
- Unfortunately, a previous injury raises the risk of a subsequent injury.
- Age.
- Sex.
Running vs. No Running
- The risks from any amount of running are always lower than from doing no running at all.
- On average, runners live three years longer than non-runners.
- Those who engage in high amounts of running still have health benefits compared to non-runners, but there is probably a point of diminishing returns.
Shedding the Pounds
- Runners tend to weigh less than walkers.
- This could be because thinner people are more likely to run, but a study by Williams suggests running helps shed excess weight.
- It showed that reductions in body mass index (BMI) were significantly greater from running compared with walking when these activities were matched for energy expenditure.
- This could be due to a greater increase in metabolic rate after more intense exercise.
So, Which is Best?
Research demonstrates that both running and walking are good for us, as they both:
- Improve cardiorespiratory fitness;
- Reduce blood pressure;
- Reduce BMI; and
- Aid with the risk of a host of diseases.
From a time perspective, running has the edge because you can do more exercise in a given time. That said, if you expend the same amount of energy when you walk, the benefits are quite similar.
The choice is yours!
