Lecture 6 - Work Physiology

Question 1

goals of work physiology

Answer 1

to ensure worker can persorm tasks efficiently and safely within the environment
- > to ensure efficiency
* to monitor energy expenditure and avoid access fatigue
- > to ensure safety
* do not push people beyond their physical limitations

Question 2

human work capacity data can be divide into which 4 ares

Answer 2

1. the epidemiological approach
2. the physiological approach
3. the biomechanics approach
4. the psychophysical approach

Question 3

epidemiological approach of human work capacity

Answer 3

based upo identifying the frequency distribution and possible control strategies of illness and injury for a given population

Question 4

physiological approach to human work capacity

Answer 4

concerned with analyzing energy demands of the musculoskeletal system for work activities and reducing the energy expenditure of these work activities

Question 5

biomechanical approach to human work capacity

Answer 5

• > concerned with determining forces exerted upon musculoskeletal system during work
• > predicts maximal, low and frequency capacity of individuals

Question 6

psychophysical approach to human work capacity

Answer 6

concerned with human sensations associated with external stimuli

Question 7

physical work capacity

Answer 7

energy requirements to do a task

Question 8

the goal of ergonomics in the design of the physical component of jobs

Answer 8

to minimize unnecessary and possibly harmful stressors

Question 9

are people who do physically demanding jobs healthier than desk workers

Answer 9

they’re more physically fit and healthier than there less active counterparts but they’re at a greater risk of fatal heart attack

Question 10

how do you assess labour demands and workers capacities

Answer 10

• > metabolic function
• > cardiovascular function
• > respiratory function
• > strength and mobility assessments

Question 11

metabolism

Answer 11

body takes in food and drink which contain chemically stored energy and converts them into mechanical energy

Question 12

basal metabolic rate

Answer 12

minimum energy required to meet the metabolic demands of the body at rest
- > index of general level of activity of an individuals body metabolism determined by measuring the oxygen intake in the basal state (absolute rest but not asleep

Question 13

resting metabolic rate

Answer 13

• > often difficult or impractical to achieve highly controlled conditions needed to measure basal metabolism
• > depending on the conditions, resting metabolism is around 10-15% higher than basal met.

Question 14

work metabolism

Answer 14

increase in metabolism from resting to work
- > increase above resting levels represents the amount of energy needed to perform work

Question 15

workload measurements

Answer 15

can be asses indirectly by recording the uptake of oxygen that is necessary for the oxidation of nutrients
- > energy consumption is measured in kilojoules

Question 16

work energy consumption

Answer 16

(energy consumption while working) - (resting consumption or basal met.) = work Joules

Question 17

classification of work demands (energy expenditure)

Answer 17

see slide 27

Question 18

what to consider when designing heavy human work

Answer 18

• > whether it is necessary for hard physical labour to be done by humans vs machine
• > try to alleviate the workload as much as possible
• > provide rest breaks, encourage taking time off from work as needed

Question 19

how do we measure work load

Answer 19

• > when energy requirements of work are low, measuring the workers O2 consumption provides little information
• > HR is easier to obtain and may be useful tool
• > Other measures (muscle activation - EMG; brain activities - EEG)

Question 20

3 kings of worker judgement scales

Answer 20

*different ways to assess satisfaction w/work conditions is to ask workers for their opinions via:
- > ordinal
- > interval
- > ratio

Question 21

ordinal judgement

Answer 21

arrange judgement in rank order, they also have statements of of “higher” or “lower”

Question 22

interval judgement

Answer 22

require judgments set in sets that are equal distances from each other

Question 23

ratio judgement

Answer 23

intervals scaled that are anchored by an absolute zero, therefore the numbered responses in ratio scales allow mathmatical calculations

Question 24

Nordic Questionnaire

Answer 24

consists of 2 parts:
- > general information
- > focuses on region of the body
* uses a sketech of the body divided into 9 regions
* asks in one is experiencing musculoskeletal problems in those areas

Question 25

factors that influence work performance

Answer 25

• > heat
• > cold
• > age
• > time of day (circadian rhythms)

Question 26

steps for how to fit work to worker

Answer 26

1. make work easy to do, avoid fatiguing postures and highly repetitive tasks
2. Ask people for their opinions and judgments of the conditions of their work
3. Strive to improve

Question 27

craft brewery example discussed in class

Answer 27

• > purpose was to examine the different workstations for potential risks of injuries specifically related to repetitive motions and manual materials handling
• > usednordic Questionnaires, hand grip dynamometer, fitbit, gopro
• > results were that certain tasks were alot more physically demanding than others and that this poses a potential risk of injury (Cellar 1 and Bottler 2 expended most energy but drivers got the most steps)