36= bike! Flashcards
Fitting a bike needs to be done in a certain order. Arrange the following steps in the order they should be fitted:
Seat fore/aft position Frame size Seat height Handlebar height Seat width Seat tilt Handlebar width Foot position on pedal
- Frame size
- Seat width
- Seat height
- Foot position on pedal
- Seat fore/aft position
- Seat tilt
- Handlebar width
- Handlebar height
True or false: when getting your bike fitted, you should wear loose-fitting clothing and normal shoes to make sure you’re comfortable for the process
False - wear cycling shorts and shoes
To determine frame size, have the patient stand against a wall with a (2/4/6) inch thick book between their (armpits/legs/knees), making sure it’s in contact with the bottom of their ____________.
Next, mark the wall where the (top/bottom) of the book is and measure from the mark to the floor.
Multiple this distance by (0.1/0.65/0.8). This is the frame size.
2" Legs Shorts Top 0.65
What is the most important angle when assessing frame dimensions?
A) Head angle
B) Seat angle
D) Stay angle
D) Down tube angle
B - should be 72-74deg to ensure patella is over pedal spingle when crank is forward and horizontal
True or false:
Your patient has correctly chosen the correct frame size. However, they have unusually long femurs relative to their tibia. The patient should therefore choose a frame that has a small seat angle
True
Long femur - smaller angle
Short femur - larger angle
If the correct size of frame has been chosen there should be around \_\_\_\_\_\_\_ inches ofseat post showing when the seat height is adjusted. A. 1-2 B. 2-3 C. 4-5 D. 6-7
C
Too much post showing: dangerous bc there may be little seat post in seat tube, can snap causing rider to fall
Too little post: can’t lower seat post enough to reach pedals
A minimum of (3/6/9) inches of clearance is required when straddling the top tube of a mountain bike. Why?
3; Common to be forced off the seat when mountain biking - need to be able to get feet on the ground easily
How can you determine the frame size of a mountain bike?
Measure inseam length`
Why is the head tube steeper in mountain bikes?
Greater steering responsiveness
Why is the crank arm often longer in a mountain bike vs road bike?
To improve the moment arm for climbing steep grades
How do you determine the optimal saddle height?
Hold 2” book between legs in front of a wall. Mark top of book then measure to floor. (same as with determining frame size)
Multiply by 0.88-1.09 (depends on comfort)
Once the seat height has been chosen, the angle at the knee should be \_\_\_\_\_ degreesof flexion, when the crank is at the bottom dead center. A. 5-10 B. 10-20 C. 25-30 D. 35-45
C
What structures are negatively affected if seat height is too high? Too low?
High: hyperextension of knee causes stretching of musculature and posterior knee pain
Low: overworking quads causes compression of patella and anterior knee pain
True or false: When the cleats are adjusted, the first metatarsal head should sit right over the top of the pedal axle.
True
If a patient reports having calf/achilles pain, what modification can be made to require less muscle activation when pedaling? What is the drawback?
Place met head in front of the axle to produce shorter moment arm at the ankle joint
Con: more difficult to pedal at higher cadence
True or false: If the correct saddle width has been chosen, the ischial tuberosities will be located justlateral to the seat on both sides.
False - should be on the seat
To determine fore/aft position, move the seat forward or backward until the patella lines up with the _____________ ______________ when the crank is in the (forward/backward) (vertical/horizontal) position
Pedal spindle; Forward; Horizontal
A patient tells you they are planning to do a long bike ride today which involves climbing a huge hill. You suggest to they move their seat (forward/backward) to maximize torque
Backward
What happens if the seat is too far back? Too far forward?
In both scenarios, some force is being wasted and not contributing to pushing pedal down.
Too far back: forces trying to “stretch” the crank shaft
Too far forward: forces trying to “compress” the crank shaft
If a patient has a leg length discrepancy you should adjust for the (short/long) leg.
If they have a short tibia, you can use a __________ in their shoe or a ______ on the pedal.
If they have a short femur, you can adjust with _________________ position of the foot on the pedal.
Long; lift; shim; fore/aft
A patient has a short right femur. How can you adjust their bike to avoid injury?
Adjust seat height to match right (long) femur side. Then move cleat on short femur side toward the toe so foot can reach pedal without extending leg.
Note: this increases the moment arm on the ankle joint and may lead to excess strain on the posterior compartment of the right leg
True or false: The seat of the bike should be angulated upwards to avoid causing urogenitalproblems from the seat causing pressure on the perineum.
False - should be angled downward. Upward often causes LBP
How high should the handlebars be relative to the saddle? A) 1-2 inches higher than the saddle B) Same height as saddle C) 1-2 inches lower than the saddle D) 3-4 inches lower than the saddle
C - unless its a really tall cyclist then will be as much as 4 inches
Ideally, the PSIS and shoulders should be at the same height. What is an exception to this?
Rider is experiencing hand numbness - should raise handlebars
True or false: the distance between the saddle and handlebars is a matter of personal preference
True (but in general the riders nose should intersect with the head tube where it splits with the front forks, and arms should be bent to about 15deg)
