Anatomical position, planes and movement practice questions.

A sports scientist rates the somatotype of every athlete in a junior rowing squad. What does the resulting three-number rating describe?

• The share of the energy the athlete draws from each of the three energy systems
• The athlete's rank on three fitness tests relative to the rest of the squad
• The percentage of type I, type IIa and type IIx fibres in the athlete's muscle
• The relative fatness, musculoskeletal robustness and linearity of the physique

Answer: The relative fatness, musculoskeletal robustness and linearity of the physique

Somatotype describes the shape of the physique on three separate ratings, endomorphy, mesomorphy and ectomorphy, each scored on its own scale rather than as a share of a total. The rating is descriptive anthropometry: it records the physique an athlete brings to the event and does not grade it as good or bad.

A sports scientist reports the sum of eight skinfolds for every player in a squad instead of converting it into a percentage of body fat. What is the main advantage of reporting the raw sum?

• It turns the measurement into a value that can be compared across different populations
• It removes the measurement error that comes from the technician taking the skinfolds
• It shows how fat is distributed around the body, which percentage body fat also shows
• It avoids the extra error added by a prediction equation built on another population

Answer: It avoids the extra error added by a prediction equation built on another population

Converting skinfolds into a percentage of body fat requires an equation derived from a different sample, and that step adds error the raw sum does not carry. Tracking the sum across a season answers the practical question of whether fatness is changing without claiming a precision the method cannot deliver.

A goalkeeper diving to her right turns the sole of the trailing foot so that it faces away from the midline of the body. Which joint action is this?

• Inversion at the ankle
• Plantar flexion at the ankle
• Lateral rotation at the hip
• Eversion at the ankle

Answer: Eversion at the ankle

Eversion turns the sole outwards and inversion turns it inwards towards the midline; the pairing is easiest to keep straight by remembering that a classic lateral ankle sprain is a forced inversion. Both occur mainly at the subtalar joint rather than at the ankle hinge itself.

At the end of a routine a gymnast lowers her straight arms from out to the sides at shoulder height back down to her sides. Which joint action occurs, and in which plane?

• Extension at the shoulder, in the sagittal plane
• Adduction at the shoulder, in the frontal plane
• Abduction at the shoulder, in the frontal plane
• Medial rotation at the shoulder, in the transverse plane

Answer: Adduction at the shoulder, in the frontal plane

Moving the arm down towards the midline from a sideways position is adduction, which occurs in the frontal plane about the anteroposterior (sagittal) axis. Lowering the arms from in front of the body would instead be extension in the sagittal plane, so the starting position decides the answer.

During the cocking phase of a tennis serve the upper arm turns so that the front of the humerus rotates away from the midline of the body. Which joint action is this?

• Medial rotation at the shoulder
• Horizontal abduction at the shoulder
• Lateral rotation at the shoulder
• Circumduction at the shoulder

Answer: Lateral rotation at the shoulder

Rotation away from the midline is lateral, also called external, rotation, and it occurs in the transverse plane about the longitudinal axis of the humerus. Circumduction is not a rotation at all but a cone-shaped combination of flexion, abduction, extension and adduction.

During the swing phase of a sprint stride the toes are drawn up towards the shin so that the foot clears the track. Which joint action is this?

• Plantar flexion at the ankle
• Dorsiflexion at the ankle
• Eversion at the ankle
• Flexion at the knee

Answer: Dorsiflexion at the ankle

Dorsiflexion decreases the angle between the dorsum of the foot and the shin and occurs in the sagittal plane about the mediolateral axis. Plantar flexion is the opposite action and is what drives the body forward at toe-off.