Evaluation tools for the Ciclovía Recreativa

Estimation of physical activity levels in the Ciclovia Recreativa

What is an estimation of physical activity levels?

In order to estimate the levels of physical activity in the Ciclovía Recreativa, an epidemiological study is carried out using a direct observation instrument.

What is its purpose?

Through this study it is possible to estimate how much the Ciclovía Recreativa contributes toward the meeting physical activity requirements established by the CDC. This consists of a useful tool for the objective evaluation of the benefit the program has in terms of promoting health and preventing disease. At the same time, the information derived from studies like this can be used in order to advocate for the program before local authorities.

What steps should be followed?

Step 1: Basic Definitions
Before starting, it is important to make clear a few basic definitions that you will use in the development of this study.

1.MET:
A metabolic equivalent (MET) is a useful measure that describes the energy spent during a given activity. It is determined by dividing the energy spent during a given activity by the energy spent during rest.

For example, an activity with a MET value of 5 means that it requires spending five times the amount of energy needed during rest.

2.MET-Minutes:
MET-minutes are obtained by multiplying the MET value of an activity by the time in minutes in which the activity was carried out.

For example, carrying out a 5 MET activity for 30 minutes results in 150 MET-minutes of physical activity (5 X 30 = 150).

3.Physical activity intensity levels:
Physical activity is classified into to light, moderate and vigorous intensity.  This classification is made according to the energy spent during the activity that is according to its MET value. For adults, activities are classified in the following manner 17:

Table: Physical Activity Intensity Levels

Physical Activity Recommendations
The Department of Health and Human Services of the United States recommends that individuals engage in at least 150 minutes of moderate physical activity every week 18. Studies have shown that this frequency and level of physical activity can improve health and reduce the risk of cardiovascular disease, diabetes type 2, some types of cancer, osteoporosis and depression.  It is recommended to engage in 500-1000 MET-minutes of physical activity weekly.18

Step 2: Definition of Activities
This step will define the activities to observe during the Ciclovía Recreativa and establish an intensity level for each one.

In case there are previous surveys, it is useful to make use of the information on the type of activities carried out in the Ciclovía Recreativa (walking, cycling or skating) and the average time in which each activity is carried out. These data will contribute to the later analysis.

Data Collection Process

1.Personnel chosen to carry out the count should receive training. The number of people and their tasks will be determined by the counting method that will be used. In the case of Bogotá, eight people were used for each counting point, two in charge of the SOPARC counters, four in charge of the hand counters, and two in charge of counting by paper and pencil. Two collections of data were obtained by each counting method and for each activity category.

2.Random selection of two measurement points, previously stratified by the number of recorded participants. The data will be taken at the points with the highest number of participants at the peak hour of circulation. In established points, the reliability of the instruments will be evaluated and their validation carried out. The instrument's reliability refers to the instrument's capability of providing similar measurements under identical conditions, meaning they are reproducible. On the other hand, the validation of the instrument refers to how comparable the measurement taken by an instrument is to the measurement of an instrument considered to be the 'gold standard'.

3. The two points will be evaluated on two different Sundays, carrying out simultaneous measurements of 15 minutes twice an hour throughout the duration of the Ciclovía (from 7a.m. to 2 p.m.). The counting consists of recording on the SOPARC counter every time an individual passes by a point 'X' engaging in one of the activities defined in Table 11.  In addition to the measurements carried out with the SOPARC counter, the hand counter and paper and pencil counts are conducted at the same time.

4. Entering the Information in a Database: In a spreadsheet, you should construct a table that contains the collected information, organized in a  matrix like the following:

How is the form filled out?

1. First enter the location of the count, the description of the place of observation, the start time of the count, the evaluator and counting method being used.
2. Next enter the number of individuals counted in each category (activity) by each observer. Finally, enter the stop time of the count and any observations.
3. It is important to take into account the order of the counts, meaning, having the sequence of the counts present and the time of each one. It helps to number them, in order to align the entered data with the film of the count, if that is being conducted.
4. Tabulate the date in a simple Excel spreadsheet. They are classified by physical activity category and counting method. The goal is to obtain the total values of the counts organized in a matrix that allows them to be transferred to whatever program you are using for analysis. For example: