initiating rotation while airborne 1. reaction rotation 2. cat rotation 3. twist from a somersault
TRANSCRIPT
Initiating Rotation while Airborne
1. Reaction Rotation1. Reaction Rotation
2. Cat Rotation 2. Cat Rotation
3. Twist from a somersault3. Twist from a somersault
Reaction Rotation to Initiate Twist Rotation while airborne L is constant and while airborne L is constant and ΣΣT = 0T = 0 rotation action in one direction causes a rotation rotation action in one direction causes a rotation
reaction in the opposite directionreaction in the opposite direction 360° full turn/twist requires 8 series of steps 360° full turn/twist requires 8 series of steps
alternating alternating II during arm swing/recovery during arm swing/recovery HJ clearing trailing body parts [straddle, flop]HJ clearing trailing body parts [straddle, flop]
Cat Rotation to Initiate Twist Rotation
Page 505 FIG 15.8
Page 503 FIG 15.6
Cat Rotation to Initiate Twist Rotation
1.1. A.A. place lower & upper place lower & upper axes at an axes at an
2.2. B.B. twist upper body, lower twist upper body, lower body has small reaction body has small reaction
3.3. C.C. twist lower body, upper twist lower body, upper body has small reactionbody has small reaction
page 505 FIG 15.8
180180° ° half turn/twist requireshalf turn/twist requires3 steps as follows:3 steps as follows:
Somersaultto Initiate a Twist
1.1. from symmetrical position, from symmetrical position, initiate layout back sommieinitiate layout back sommie(establish (establish LL about ML axis) about ML axis)
2.2. move to asymmetrical move to asymmetrical position [drop rt. arm]position [drop rt. arm]
page 506 FIG 15.9
- this reduces - this reduces II on rt. side of body on rt. side of body about ML axis on that about ML axis on that sideside
- nutation (tilt of body) results - nutation (tilt of body) results and a twist beginsand a twist begins
Somersault to Initiate Twist Rotation most effective of the 3 methods of initiating a most effective of the 3 methods of initiating a
full twist (360full twist (360°)°)
multiple twists (720multiple twists (720° rotation or more)° rotation or more), , performer usually initiates some of the twist performer usually initiates some of the twist from the ground (Ffrom the ground (Freactionreaction) in addition to the ) in addition to the airborne maneuversairborne maneuvers
(symmetrical to asymmetrical during the (symmetrical to asymmetrical during the somersault action)somersault action)
“Kicker” ramp places body
in position for g to apply a T
to initiate a back sommie
Left photo
symmetricalsymmetrical
Right photo
asymmetricalsymmetrical
Altering k: radius of gyrationpage 511
FIG 15.13
atight tuck
elayout
Altering k - radius of gyration
TABLE 15.1 on page 510TABLE 15.1 on page 510- read across from left to right- read across from left to right
Example from Table 15.1:Example from Table 15.1:
moving from position moving from position aa to position to position ee diminishes by almost 75 diminishes by almost 75 [from 1.00 to 0.28] [from 1.00 to 0.28]
Manipulating Rotations in Sport
Manipulating Rotations in Sport
Manipulating Rotations in Sport
page 515
FIG 15.17
Manipulating Rotations in Sport
More elongated = Slower Rotation about ML axisLess elongated body = Faster RotationReaction Rotation to Clear Trailing Body Parts
Gymnastics Tumbling Skills
Less Skilled Highly Skilled
low vlow vvertvert due to: due to: power + power + takeoff takeoff
less air timeless air time low low due to:due to:
power + power + I @ takeoff I @ takeoff largerlarger k in flightk in flight
high vhigh vvertvert due to: due to: power + power + takeoff takeoff
more air timemore air time high high due to:due to:
power + power + I @ takeoff I @ takeoff smallersmaller k k in flightin flight
Sample Tape: Aid in Prep for Test 1 copy of a sample tape located in each of the 2 video 1 copy of a sample tape located in each of the 2 video
viewing booths (VCR in middle booth not working) viewing booths (VCR in middle booth not working)
booths located in Thames Hall room booths located in Thames Hall room 2120A across 2120A across the hall from the Computer Labthe hall from the Computer Lab
each booth can hold up to 3 personseach booth can hold up to 3 persons
ABOUT THE VIDEO EXAM
1.1. Exam held in Natural Science Room 145 Exam held in Natural Science Room 145
2.2. Video Exam is 45 minutes long coveringVideo Exam is 45 minutes long covering
3.3. 9 skills, 3 questions per skill (n=27 questions)9 skills, 3 questions per skill (n=27 questions)
4.4. 5 minutes allowed to answer 3 questions per skill5 minutes allowed to answer 3 questions per skill
5.5. Exam Value 25% of final course gradeExam Value 25% of final course grade