Expending 100 Calories (7.5 minutes at 16 km/h) in a single commute trip is associated with a mortality benefit of about 20%.

Obesity and Heart Disease Risk

Rates of overweight and obesity are lower in neighbourhoods located closer to downtown areas. Findings from Toronto show that the rates of diabetes follow a similar pattern. A 5 per cent increase in neighbourhood walkability is associated with a 32 percent increase in minutes spent walking and cycling. Each hour spent in a car increases the risk of obesity by 6%.

Based on an Automobile Median Speed of 16.6km/h:

  • .06 / 16.6 = 0.004 per km

Source: Peel Long Range Transportation Plan – Update 2012
https://www.peelregion.ca/planning/residents/transportation/LRTP-Report.pdf

“Cyclists who cover at least 40 kilometres each week halve their risk of heart disease when compared with those who do not cycle “

For the purposes of a Social Economic Cost-Benefit Comparison on a per km basis: 1km of cycle travel reduces risk of heart disease by 1.25%.

Source: Cycling: towards health and safety. Oxford: Oxford University Press, 1992.

Premature Death

“Minimal adherence to current physical activity guidelines, which yield an energy expenditure of about 1000 kcal x wk(-1) (4200 kJ x wk(-1)), is associated with a significant 20-30% reduction in risk of all-cause mortality.”
https://www.ncbi.nlm.nih.gov/pubmed/11427772

“Furthermore, an increase in energy expenditure from physical activity of 1000 kcal (4200 kJ) per week or an increase in physical fitness of 1 MET (metabolic equivalent) was associated with a mortality benefit of about 20%.”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1402378/#r14-23

Daily Kcal Expenditure (Dkc)

  1. Dkc = 1000 kcal / 5
  2. Dkc = 200 kcal

A typical commute week of 5 commuting days, with a daily expenditure of 200 kcal (Calories), or 100 Calorie work/return trips, is associated with a mortality benefit of about 20%.

Calculating Kcal Expenditure of a Sample Commute

The expenditure of Calories is a function of weight, distance, and time, and for this document will be calculated using this formula:

  • Joules = 0.5 * (Rider KG + Bike KG) * POWER(Trip Distance m / Trip Time sec., 2)
  • Calories = (Joules / 4184) * Trip Time secs

Note: This formula does not take drag or coasting into consideration.

Example

  • The average cycling speed in Brampton is 16 km/h.

Given these inputs, a minimum 100 Calorie trip can be calculated this way:

Joules

  1. Joules = 0.5 * (81.6 + 13) * POWER(2,000 m / 450, 2)
  2. Joules = 0.5 * (94.6) * POWER(4.444, 2)
  3. Joules = 0.5 * 94.6 * (4.444)(4.444)
  4. Joules = 0.5 * 94.6 * 19.749
  5. Joules = 934

Calories

  1. Calories = (Joules / 4,184) * Trip Time secs
  2. Calories = (934 / 4,184) * 450
  3. Calories =  0.223 * 450
  4. Calories = 100

Based on this estimation, it takes about 7.5 minutes of sustaining 16 km/h (2,000 m over 450 seconds) to expend 100 Calories in a single commute trip, which in turn is associated with a mortality benefit of about 20% over the course of a week.

  • 20% / 2km – 10% benefit per km