The differing ages that a person has will affect the person’s total vital capacity of their lungs by determining whether they will have a larger or smaller vital capacity if they are either younger or older, therefore the age of people have will be our independent variable.
The weight of a person will affect the result of how large their lung’s vital capacity will be, thus this is a controlled variable and will need to be kept constant.
The height of a person could also have an effect on the results of their vital capacity so this will also need to be kept constant.
The amount of exercise that a person partakes in can also have an effect on their vital capacity, so this will also need to be kept constant.
The possibility that a person is a smoker and their frequency in smoking could also have an effect on their lung’s vital capacity, therefore this must also be kept constant.
The gender of a person can also affect their total vital capacity, so this must also be kept constant.
Someone’s race or ethnicity could possibly have an effect on their vital capacity; therefore this must also be kept to a constant.
Health issues and problems that a person has could possibly have an effect on their vital capacity, so this must also be kept constant.
A person’s occupation could also have an effect on their vital capacity; therefore this must be kept constant.
All these variables can affect the total size or capacity of a person’s lungs vital capacity, so the measurement of how large a person’s vital capacity is will be our dependent variable.
How to deal with the variables:-
The ages of the participants within this experiment is the independent variable and so must be adjusted. The ages of the participants will vary from 15 to 39; however, the participants will be divided into groups, which will differ from each other by three years. In other words, the ages of the participants involved will be 15, 18, 21, 24, 27, 30, 33, 36, and 39 years of age.
The manner in which I will deal with all my controlled variables is by conducting a survey and choosing a specified aspect of the variable, thereby eliminating those participants that do not fit within the categories. This is the survey in which I will conduct on participants:
Please tick the box that corresponds with your age:
15 yrs old ? 18 yrs old ? 21 yrs old ? 24 yrs old ? 27 yrs old ? 30 yrs old ?
33 yrs old ? 36 yrs old ? 39 yrs old ?
Please specify your gender:
Male ? Female ?
Of what ethnicity do you classify yourself as?
Caucasian ? African-American ? Asian ? Hispanic ? Middle Easterner ?
Pacific Islander ? Other
Approximately, how much do you currently weigh?
45-55 kg ? 56-65 kg ? 66-75 kg ? 76-85 kg ?
How tall are you currently?
160-170 cm ? 171-180 cm ? 181-190 cm ?
How regularly do you exercise?
1-3 hrs per week ? 4-6 hrs per week ? 7-9 hrs per week ? 10-12 hrs per week ?
How would you describe yourself in terms of smoking cigarettes?
Non-smoker ? minimal smoker ? moderate smoker ? intense smoker ?
Do you or your family have a history of any health problems? If so, please specify.
What is your occupation and does it contribute to any health problems in any manner?
The aspects of the variables that I choose for my controlled variables are that the participants in my experiment have to be a Caucasian male who is approximately in between 66-75 kg in weight and 171-180 cm in height, who regularly exercises between 4-6 hrs a week, who is a non-smoker and whose occupation and health history do not contribute to any current health problems.
To measure the amount of a participant’s vital capacity, a lung volume kit will be utilised.
Firstly, I will conduct the survey to find and include the participants that I want that have the specified aspects that I wanted out of my controlled variables mentioned above. I will obtain a total of three participants for each of the nine age groups that I have included in my experiment. Once this has been completed, I will provide them with the necessaries needed to conduct the experiment, such as lung volume kit, as well as instructions on how to use it, which was written by the Hubbard Scientific Vol. 6050 guide. This instructions guide is attached below. Once each participant from each age group has carried out the experiment once, they will be instructed to carry out the experiment for another two times. This will ensure that I have 9 sets of 9 measurements.
Since a person undergoes a growth period as the age, their bodily functions would become more developed, so I predict that the higher the age the participant in my experiment is, the higher their vital capacity measurement will be as they will have a larger lung capacity compared to their younger colleagues. I would also predict that since they will be having a close amount of time spent exercising; this would make it more likely that the older participants will have a larger vital capacity than the younger ones.