KNES 360: Ch 19 Speed

skills and abilities needed to achieve high movement velocities

speed

skills and abilities needed to explosively change movement direction, velocities, or modes

change of direction

the skills and abilities needed to change direction, velocity, or mode in response to a stimulus (decelerate and accelerate again)

agility

difference between agility COD

agility is in response to a stimulus - auditory or visual. COD you know where you're going

all agility is COD but

not all COD is agility

two variables that describe force relative to time available to produce force

rate of force development (RFD) and impulse

change in momentum, either accelerating or decelerating, result from a force, measured as the product of force and time

impulse

what happens when you move the force curve up and to the left

greater impulse and momentum is generated during the limited time over which force is applied

The development of maximal force in minimal time, typically used as an index of explosive strength

rate of force development

maximal contraction typically occurs at _____ms

greater than 300ms

contractions in sport occur within _____ to ____ ms

0 to 200 ms

when functional movements are performed, force is typically applied

very briefly; ~0.1 to 0.2 sec

maximum force development may require ____ to ____ seconds

0.6 to 0.8 seconds

why is max force development so important in sport

athletic/sport movements are very quick/short. you need to produce as much force as possible in a very short period of time.

you have two twin football players that can both bench 300 lbs. one of them is ballistically trained. who produces the most force?

both twins can move the same 1RM but when it comes to actual force production, the twin that is plyo/ballistic trained will produce the most force for optimal performance

heavy resistance trained athletes will have higher maximum strength but lower force production compared to

ballistic trained athlete

increase in the rate at which action potentials occur

neuromuscular activity or neural drive

increases in neural drive occur due to these two types of training

strength and plyometric training

increases in neural drive due to strength and plyo training result in

increased muscular force production and rate of force production

acute SSC actions tend to increase mechanical efficiency and impulse via

elastic energy recovery

what do chronic SSC actions do

upregulate muscle stiffness and enhance neuromuscular activation

produced by spring-like actions within the muscle

spring-mass model

how do you improve the spring mass model

speed and ballistic training; train stretch reflex

when is fatigue good

hypertrophy and endurance training

how do you increase neural drive when sprinting at high speeds

~utilize multi-joint movements exploiting elastic-reflexive mechanisms
~emphasize quality and technique, brief work bouts and frequent rest pauses

complex training

a combination of resistance training followed by plyometrics

what's the idea behind doing complex training

enhancing post-activation potentiation

what is post-activation potentiation

after activation of motor units, potential to do work increases

describe how complex training applies post-activation potentiation

~perform nonfatiguing, lower RM squat and then perform verticals. the hope is that you jump higher because the motor units are already fired up from the weight lifting

benefits of complex training

jumping higher allows for more work to be done. more work means more adaptation. overload principle

what is the rest period for complex training

very low to none. if you rest between the squat and the vertical jump you will not reap the neural benefits because by the time you do the verticals the motor units are already "sleeping" again

2 factors that determine sprint speed

stride length and stride rate

more successful sprinters tend to have

longer stride lengths and more frequent stride rate

2 primary limiting factors influencing sprint performance

RFD and proper biomechanics

since foot contact during sprinting is very brief, how do you get the advantage?

force development: the stronger the force development, the bigger the push off between strides

stride length of elite male sprinters

2.7 m

stride length of novice sprinters

2.56 m at max velocity

stride rates of elite male sprinters

4.63 steps per second

stride rates of novice sprinters

4.43 steps per second

problems with a stride length that is too long

too long creates a breaking force, kills momentum

which is more easy to manipulate, stride length or frequency

stride frequency

training goals if you want to improve running speed

~emphasis on brief ground support times as a means of achieving rapid stride rate
~emphasis on further development of SSC

high achievers at top speed sprinting produce high forces in a shorter stance phase using

SSC

The transfer of strength improvements to sprinting may require an emphasis on the ___________ of training

specificity of training

transfer of training effect deals with the degree of performance adaptation and may result from

~similarities between movement patterns
~peak force
~RFD
~acceleration
~velocity patterns
~sporting environment

examples of assistance training (overspeed training)

downhill running, rope towing, bungee cord pulls

assistance training is mainly done to

increase stride rate

examples of resistance training for speed development

sled towing, wind resistance, incline sprinting, and sled pushing

resistance training for speed development is done to

improve RFD and stride length (some stride frequency)

how does resistance training for speed development help improve stride length

increased RFD and power. the more power you can put into a push off during a spring the farther you can go

strength methods to develop agility

plyos, lunges, squats, etc.

change of direction methods to develop agility

COD drills

how does perceptual cognitive ability help develop agility

improve anticipation and decision making time; involves interpretation of cues

i.e. running patterns between cones/ to and back from cones; you know where you're going

COD drill

basic drills that involve bends rather than sharp cutting movements

maneuverability

i.e. running patterns that involve COD without knowing where you're supposed to be going; spatial and temporal uncertainty; interpretation of visual or auditory cues

agility

when should athletes conduct speed and agility tasks

early in a training session

how many speed/agility sessions per week

2 to 3

how long are speed/agility sessions typically

about 15 minutes

rest periods for speed/agility training

30 sec to 3 min

work rest ratio for speed/agility training

1:5-1:12-1:20 depends on drill

why do you do plyos for long distance running

~improve running economy
~improve muscle/tendon stiffness
~increase stride length

program development

1. needs analysis & match tests
2. strengths/weaknesses
3. plan areas of needs
4. time distribution
5. plan