Biomechanics and Anthropometry Flashcards
7 cards from real AEP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Biomechanics and Anthropometry flashcards as text
Which type of anthropometric data accounts for the range of body positions and movements that occur during actual work tasks?
Answer: Functional (dynamic) anthropometry
Functional or dynamic anthropometry measures body dimensions during movement and task performance, capturing the actual reach envelopes and postural variations encountered in real work conditions.
In a static biomechanical model, the sum of moments about a joint in equilibrium must equal:
Answer: Zero
In static equilibrium, the algebraic sum of all moments (torques) about any joint must equal zero, a fundamental principle used to solve for unknown muscle and joint forces.
Which muscle group serves as the primary antagonist to back extensor muscles during loaded forward flexion?
Answer: Abdominal muscles (rectus abdominis and obliques)
The abdominal muscles create an opposing moment that helps control forward flexion and contribute to intra-abdominal pressure, reducing the load on lumbar extensors during lifting.
The 95th percentile male value means that:
Answer: 95% of males fall below this measurement
A 95th percentile value means that 95% of the reference population (in this case, males) have a measurement at or below that value, while only 5% exceed it.
Static strength is best described as:
Answer: The maximum force sustained against a fixed, immovable resistance over a brief period
Static (isometric) strength is the maximum force a person can exert against a fixed resistance over a brief, standardized time period, commonly used in job demands analysis.
When performing an ergonomic assessment that requires comparison of worker dimensions to a workstation, which data source is most appropriate for a US adult workforce?
Answer: All of the above are valid US adult anthropometric data sources
ANSUR II, NHANES, and CAESAR are all recognized sources of US adult anthropometric data; selecting the most appropriate depends on the workforce demographics being modeled.
Intra-abdominal pressure (IAP) during lifting is believed to contribute to spinal stability primarily by:
Answer: Creating an extension moment that partially offloads the erector spinae
Elevated intra-abdominal pressure acts like an inflated balloon in the abdominal cavity, generating a slight extension moment that reduces the demand on the lumbar extensor muscles and therefore spinal compression.