Last update and review: November 28, 2020.
A short summary.
Walking is an excellent option if you need to alternate your more vigorous physical activity with something safe. VO2 is high during both self-selected comfortable and intentionally “brisk” walking. Calculating your walking distance, speed, heart rate is informative. Monitoring your joints and ligament recovery may be therapeutic.
If you need to alternate your high-impact aerobic and other exercise with a safer physical activity, walking is an excellent option.
Many talk about walking as an activity suited for generally sedentary people. Walking can, however, be an excellent option for those who need to alternate their main aerobic activity with something else. Indeed, runners, for example, are prone to injuries. To a degree, frequent injuries can be explained by the fact that running is practiced on a daily basis. Walking at a comfortable pace of up to 70% of the maximum heart rate and at a “brisk” pace of 80% of the maximal heart rate is an excellent safe alternative to high-impact aerobic and other exerecise. Beware, however, that if heart rates above 120 bpm are maintained for prolonged periods of time, hormonal axes, e.g. hypothalamus-pituitary-gonades, may be affected.
“Walking to health.”
We are exploring walking more as a recovery and healing option for athletic population. But benefits of walking for general population are remarkable. Morris and Hardman, 1997 (6), wrote an excellent introduction on the subject. We reproduce a longer passage from it:
Walking, faster than customary, and regularly in sufficient quantity into the ‘training zone’ of over 70% of maximal heart rate, develops and sustains physical fitness: the cardiovascular capacity and endurance (stamina) for bodily work and movement in everyday life that also provides reserves for meeting exceptional demands. Muscles of the legs, limb girdle and lower trunk are strengthened and the flexibility of their cardinal joints preserved; posture and carriage may improve.
Walking is also the most common weight-bearing activity, and there are indications at all ages of an increase in related bone strength.
Walking is convenient and may be accommodated in occupational and domestic routines. It is self-regulated in intensity, duration and frequency, and, having a low ground impact, is inherently safe.
Unlike so much physical activity, there is little, if any, decline in middle age. It is a year-round, readily repeatable, self-reinforcing, habit-forming activity and the main option for increasing physical activity in sedentary populations.
A recommendation by Morris and Hardman, 1997 (6): “a gradual progression from slow, to regular pace and on to 30 minutes or more of brisk (i.e. 6.4 km/h) walking on most days.”
As general policy, a gradual progression is indicated from slow, to regular pace and on to 30 minutes or more of brisk (i.e. 6.4 km/h) walking on most days.
A pace that meets the recommendations for moderate intensity is 1.34 to 1.79 meters per second, or 4.82 to 6.44 kilometers per hour, or 3 to 4 miles per hour.
Taylor et al., 2010 (5):
a pace that meets the public health recommendations for moderate intensity physical activity (1.34-1.79 ms-1).
Speed and exercise intensity in the study by Murtagh et al., 2002 (4).
Murtagh et al., 2002 (4), investigated self-selected speed of recreational walkers and their interpretation of “brisk walking”.
It turned out that the self-selected speed, which was between 1.55 and 1.6 meters per second, resulted in an exercise intensity of almost 60% of VO2max and a heart rate of 67% of the maximum. A “brisk” walking speed observed was 1.79 meters per second in a parc and 1.86 meters per second on a treadmill. The “brisk” walking speed equated to almost 69% of VO2max and 78.5% of the maximum heart rate.
Murtagh et al., 2002 (4):
Methods.
The walking speed of 82 adults was covertly observed in a public park. Fifty-nine of these participants demonstrated their interpretation of “brisk walking” and the speed was noted. Eleven of these subjects subsequently walked on a treadmill at their observed and “brisk walk” speeds. Heart rate (HR), respiratory gases, and ratings of perceived exertion (RPE) were measured.
Murtagh et al., 2002 (4):
Subjects
82 subjects aged between 21 and 74 years (28 men, 54 women) were observed in a public access park in Northern Ireland..
Subjects (n = 82) reported walking 4.82 times per week, for approximately 54.46+/- 24.6 min.
Eleven of these subjects, all females, subsequently walked on a treadmill at their observed and “brisk walk” speeds.
Rate of perceived exertion (RPE), VO2max and heart rate in the treadmill exercise.
Self-selected walking speed that equates to almost 60% of VO2max is NOT perceived as overexerting.
Murtagh et al., 2002 (4):
Interestingly, the mean rating of perceived exertion during observed habitual walking speed was 11.5 (11=fairly light), indicating that individuals do not perceive their usual walking pace to be overexerting.
Murtagh et al., 2002 (4):
Because an individual’s physiological stress related to walking speed is a function of VO2max [22], Spelman’s group of walkers were capable of sustaining a higher pace (1.78 0.19 m/s). However, Spelman et al. studed “exercise walkers” whose mean VO2max was approximately 4 ml/(kg*min) higher than the recreational walkers of the present study.
The physiological threshold of ‘comfort’ represents 70% of maximum heart rate.
Morris and Hardman, 1997 (6):
The physiological threshold of ‘comfort’ represents 70% of maximum heart rate.
The average middle-aged person should be able to walk 1.6 km comfortably on the level at 6.4 km/h and on a slope of 1 in 20 at 4.8 km/h, however, many cannot do so because of inactivity-induced unfitness.
Using the adjective “brisk” when prescribing walking evokes a more vigorous intensity of exercise.
Murtagh et al., 2002 (4):
The central finding of this study is that the pace and relative intensity selected by this group of recreational walkers is of moderate intensity, and instructing them to walk“briskly”prompts more vigorous activity.
Calculating your working speed.
Many online maps have good “itinerary calculation”. You can use them to calculate your walking distance and then to use the distance to calculate your speed.
What is your “brisk” walking speed? Can you sustain 7.5 kilometers per hour for 40 minutes?
What is your comfortable walking speed?
What is your heart rate during brisk and comfortable walking?
How do your joints feel after a session of brisk walking and after comfortable walking?
Tips to calculate distance and speed.
The published literature uses meters per second to measure walking speed. Kilometers or miles per hour may be more familiar. Below, there are some pieces of information that should be helpful for converting distances and speeds back and forth.
1 meter per second = 3.6 kilometers per hour, exactly. 1 meter per second = 2.23694 miles per hour, approximately.
The definition of the international mile, which is apparently in use in the UK, in the US, and elsewhere.
National Bureau of Standards in the US, on January 22, 1975 (3):
the international mile equals 1.609 344 kilometers, exactly.
National Bureau of Standards in the US, on January 22, 1975 (3):
The relationship 1 international nautical mile =1.852 kilometers is exact.
Other definitions of mile.
The definition of mile from Encyclopedia Britannica:
Mile, any of various units of distance, such as the statute mile of 5,280 feet (1.609 km). It originated from the Roman mille passus, or “thousand paces,” which measured 5,000 Roman feet.
The definition of nautical mile from Encyclopedia Britannica:
In 1929 the nautical mile was redefined as exactly 1.852 km (about 6,076.11549 feet or 1.1508 statute miles) at an international conference held in Monaco, although the United States did not change over to the new international nautical mile until 1954. The measure remains in universal use in both marine and air transportation. The knot is one nautical mile per hour.
A nautical mile was originally defined as the length on the Earth’s surface of one minute (1/60 of a degree) of arc along a meridian (north-south line of longitude). Because of a slight flattening of the Earth in polar latitudes, however, the measurement of a nautical mile increases slightly toward the poles.
Vuchic, 2008 (a book) (1), is a useful source on conversion of units.
Selected references:
1. Urban Transit Systems and Technology. Vukan R. Vuchic. John Wiley & Sons, Inc. 2007. ISBN: 978-0-471-75823-5.
2. Cardarelli, Francois. Scientific Unit Conversion. New York: Springer-Verlag, 2003.
A comment by Vuchic, 2007 (1):
“For more extensive coverage of units, the following book is suggested: Cardarelli, Francois. Scientific Unit Conversion.”
3. Weights and measures standards of the United States, 1976. https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication447.pdf
Accessed on November 28, 2020.
4. Murtagh et al. Prev Med. 2002 Oct;35(4):397-400.
5. Taylor et al. J Exerc Sci. 2010 Jul 15;3(3):87-96. PMID: 27182333; PMCID: PMC4738894.
6. Morris JN, Hardman AE. Sports Med. 1997 May;23(5):306-32.