Expending 100 Calories (8.5 minutes at 15 km/h) in a single commute trip is associated with a mortality benefit of about 20%.
Obesity and Diabetes
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% increase in neighbourhood walkability is associated with a 32% increase in minutes spent walking and cycling. Each hour spent in a car increases the risk of obesity by 6%.
Source: Peel Long Range Transportation Plan – Update 2012
“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.”
“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%.”
Daily Kcal Expenditure (Dkc)
- Dkc = 1000 kcal / 5
- 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.
- The 2008 mean weight of a person was 81.6 kg.
Source: 2008 Canadian Community Health Survey (subsample).
- Bicycle weights can vary, depending on style and purpose. A commuter bicycle on the heavy side is about 13kg.
Source: City bicycle. (2017, June 8). In Wikipedia, The Free Encyclopedia.
Retrieved June 14, 2017
- The average cycling speed in Brampton is 15 km/h.
Given these inputs, a minimum 100 Calorie trip can be calculated this way:
- Joules = 0.5 * (81.6 + 13) * POWER(2,125 m / 510, 2)
- Joules = 0.5 * (94.6) * POWER(4.167, 2)
- Joules = 0.5 * 94.6 * (4.167)(4.167)
- Joules = 0.5 * 94.6 * 17.364
- Joules = 821
- Calories = (Joules / 4,184) * Trip Time secs
- Calories = (821 / 4,184) * 510
- Calories = 0.196 * 510
- Calories = 100
Based on this estimation, it takes about 8.5 minutes of sustaining 15 km/h (2,125m over 510 seconds) to expend 100 Calories in a single commute trip, which in turn is associated with a mortality benefit of about 20%.