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Thursday 22 October 2015

Kinematics and Kinetics: An Applied Interpretation.


Kinematics and Kinetics: An Applied Interpretation

by Andrew Richardson





What this article will achieve is the following:

  • A better understanding of what biomechanics is and not just a term "PT's" throw around to impress their clients
  • The Difference between kinematics and kinetics - applying these principles to some sports (powerlifting, weightlifting etc.)
  • Using biomechanics in a sports science/strength and conditioning application. 

I hope you enjoy it.

Now before we begin, there is a growing trend of lifters/coaches/athletes whom refuse to learn or educate themselves on the new training methods or the science/research of training methodologies. Their excuse is usually "nah I am old school", no you're just lazy. Don't be afraid to say "I don't know what something is", no one will think any less of you in fact they are more than likely to go and help you understand it. Embrace modern day theories and leaning. Don't shut yourself off from the science. 

Lets get started with some definitions shall we;  


Biomechanics - The science concerned with the internal and external forces acting on the human body and the effects produced by these forces. So we have seen some biomechanical analysis of a counter-movement jump (vertical jump) or a squat.

Kinematics: - The branch of biomechanics concerned with the study of movement from a geometrical point of view. This can be described as a phase analysis of a movement e.g basketball. 

Kinetics - The branch of biomechanics concerned with what causes a body to move the way it does. as well as what forces are acting upon the body and cause it to move in its own way



We have Linear and Angular variables which make up biomechanics and they too have their own sub sections.

Distance and Displacement

Distance (length of the path a body follows) and displacement (length of a straight line joining the start and finish points) are quantities used to describe a body's motion. e.g. in a 400m race on a 400m track the distance is 400 metres but their displacement will be zero metres (start and finish at the same point).

Speed and Velocity

Speed and velocity describe the rate at which a body moves from one location to another. Average speed of a body is obtained by dividing the distance by the time taken and average velocity is obtained by dividing the displacement by the time taken e.g. a swimmer in a 50m race in a 25m length pool who completes the race in 71 seconds - distance is 50m and displacement is 0m (swimmer is back where they started) so speed is 50/71= 0.70m/s and velocity is 0/71=0 m/s

Speed and Velocity = distance travelled ÷ time taken

Acceleration

Acceleration is defined as the rate at which velocity changes with respect to time.
average acceleration = (final velocity - initial velocity) ÷ elapsed time

From Newton's 2nd law:

Force = Mass x Acceleration (F=MA)
Acceleration = Force ÷ Mass (A = F/M)
If the mass of a sprinter is 60kg and the force exerted on the starting blocks is 600N then the acceleration is 600 ÷ 60 = 10 m/sec²

Acceleration due to gravity

Whilst a body is in the air it is subject to a downward acceleration, due to gravity (g), of approximately 9.81m/s²

Vectors and Scalars
Distance and speed can be described in terms of magnitude (amount) and are known as scalars. Displacement, velocity and acceleration require magnitude and direction and are known as vectors.
Components of a vector



Chest Pass
Figure 1
Velocity Components




Figure 2
Let us consider the horizontal and vertical components of velocity of the medicine ball in Figure 1.

Figure 2 indicates the angle of release of the medicine ball is 35° and the velocity at release as 12 metres/second (m/sec).

Vertical component Vv = 12 x sin 35° = 6.88 m/sec
Horizontal component Vh = 12 x cos 35° = 9.82 m/sec
Let us now consider the distance the medicine ball will travel horizontally (its displacement).

Distance (D) = ((v² × sinØ × cosØ) + (v × cosØ × sqrt((v × sinØ)² + 2gh))) ÷ g

Where v = 12, Ø = 35, h = 2m (height of the shot above the ground at release) and g = 9.81

D = ((12² × sin35 × cos35) + (12 × cos35 × sqrt((12 × sin35)² + 2 x 9.81 x 2))) ÷ 9.81
D = 16.22m

Feel free to take a short break after reading that. Inb4 how do I even math bro........

Continuing on :)

The time of flight of the shot can be determined from the equation:

Time of flight = Distance (D) ÷ velocity (Vh)
Time of flight = 16.22 ÷ 9.82 = 1.65 seconds
Uniformly accelerated motion

When a body experiences the same acceleration throughout an interval of time, its acceleration is said to be constant or uniform and the following equations apply:

Final velocity = initial velocity + (acceleration x time)
Distance = (initial velocity x time) + (½ x acceleration x time²)

Moment of Force (torque)

The moment of force or torque (τ) is defined as the application of a force at a perpendicular distance to a joint or point of rotation.

Torque (τ = rFsin θ ) depends on three quantities:

the length of the lever arm connecting the axis to the point of force application (r)
the force applied (F)
the angle between the force vector and the lever arm (sin θ)

Torque and length of lever arms

• Torque – (moment of force) the turning effect of an eccentric force
• Eccentric force - force applied in a direction not in line with the centre of rotation of an object with a fixed axis
– In objects without a fixed axis it is an applied force that is not in line with object's centre of gravity
• For rotation to occur an eccentric force must be applied

Torque and length of lever arms
• In humans, contracting muscle applies an eccentric force (not to be confused with eccentric contraction) to bone upon which it attaches & causes the bone to rotate about an axis at the joint
• Amount of torque is determined by multiplying amount of force (force magnitude) by force arm

Torque and length of lever arms
• Force arm - perpendicular distance between location of force application & axis
– a.k.a. moment arm or torque arm
– shortest distance from axis of rotation to the line of action of the force
– the greater the distance of force arm, the more torque produced by the force

Torque and length of lever arms
• Often, we purposely increase force arm length in order to increase torque so that we can more easily move a relatively large resistance (increasing our leverage).
• Resistance arm - distance between the axis and the point of resistance application.

Torque and length of lever arms
• Inverse relationship between length of the two lever arms.
– Between force & force arm.
– Between resistance & resistance arm.
– The longer the force arm, the less force required to move the lever if the resistance
& resistance arm remain constant.
– Shortening the resistance arm allows a greater resistance to be moved if force & force arm remain constant.

Torque and length of lever arms
• Proportional relationship between force components & resistance components.
– If either of the resistance components increase, there must be an increase in one or both of force component.s
– Greater resistance or resistance arm requires greater force or longer force arm.
– Greater force or force arm allows a greater amount of resistance to be moved or a longer resistance arm to be used.



Torque and length of lever arms
• Even slight variations in the location of the force and resistance are important in determining the effective force of the muscle.

Torque and length of lever arms
• Human leverage system is built for speed & range of movement at expense of force
• Short force arms & long resistance arms require great muscular strength to produce movement
• Ex. biceps & triceps attachments
– biceps force arm is 1 to 2 inches.
– triceps force arm less than 1 inch.

Torque and length of lever arms
• Human leverage for sport skills requires several levers
– throwing a ball involves levers at shoulder, elbow & wrist joints.
• The longer the lever, the more effective it is in imparting velocity
– A tennis player can hit a tennis ball harder with a straight-arm drive than with a bent elbow because the lever (including the racket) is longer & moves at a faster speed.

Torque and length of lever arms
• Long levers produce more linear force and thus better performance in some sports such as baseball, hockey, golf, field hockey, etc.

Torque and length of lever arms
• For quickness, it is desirable to have a short lever arm
– baseball catcher brings his hand back to his ear to secure a quick throw.
– sprinter shortens his knee lever through flexion that he almost catches his spikes in his gluteal muscles.

Angular Kinematics

Angular distance and displacement:
When a rotating body moves from one position to another, the angular distance through which it moves is equal to the length of the angular path. The angular displacement that a rotating body experiences is equal to the angle between the initial and final position of the body.

Angular movement is usually expressed in radians where 1 radian = 57.3°

Angular speed, velocity and acceleration

Angular speed = angular displacement ÷ time
Angular velocity = angular displacement ÷ time
Angular acceleration = (final angular velocity - initial angular velocity) ÷ time
Angular Momentum

Angular momentum is defined as: angular velocity x moment of inertia

The angular momentum of a system remains constant throughout a movement provided nothing outside of the system acts with a turning moment on it. This is known as the Law Conservation of Angular Momentum. (e.g. if a skater, when already spinning, moves their arms out to the side, then the rate of spin will change but the angular momentum will stay the same).


Linear Kinetics
Kinetics is concerned with what causes a body to move.

Momentum, inertia, mass, weight and force

Momentum: mass x velocity
Inertia: the reluctance of a body to change whatever it is doing.
Mass: the quantity of matter of which a body is composed of - not affected by gravity - measured in kilograms (kg).
Weight: force due to gravity -9.81m/s².
Force: a pushing or pulling action that causes a change of state (rest/motion) of a body is proportional to mass x acceleration. It is measured in Newtons (N) where 1N is the force that will produce an acceleration of 1 m/s² in a body of 1kg mass.
The classification of external or internal forces depends on the definition of the 'system'. In biomechanics, the body is seen as the 'system' so any force exerted by one part of the system on another part of the 'system' is known as an internal force all other forces are external.

Newton's Laws of Motion

First Law: Every body continues in its state of rest or motion in a straight line unless compelled to change that state by external forces exerted upon it.

Second Law: The rate of change of momentum of a body is proportional to the force causing it and the change takes place in the direction in which the force acts

Third Law: To every action there is an equal and opposite reaction OR for every force that is exerted by one body on another there is an equal and opposite force exerted by the second body on the first
Newton's law of gravitation

Any two particles of matter attract one another with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between them

Kinetic Energy and Power

Kinetic energy is the mechanical energy possessed by a moving object.

Kinetic Energy = ½ x mass x velocity² (joules)

Power is defined as the rate at which energy is used or created from other forms

Power = energy used ÷ time taken
Power = (force x distance) ÷ time taken
Power = force x velocity

Angular Kinetics

Translation and couple

A force that acts through the centre of a body result in movement (translation). A force whose line of action which does not pass through the body's centre of gravity is called an eccentric force and results in movement and rotation.

Example - if you push through the centre of an object it will move forward in the direction of the force. if you push to one side of the object (eccentric force) it will move forward and rotate.

A couple is an arrangement of two equal and opposite forces that cause a body to rotate.

Levers

A lever is a rigid structure, hinged at one point and to which forces are applied at two other points. The hinge is known as the fulcrum. The two forces forces that act on the lever are the weight that opposes movement and a force that causes movements.

Levers
The mechanical advantage of levers may be determined using the following equations:

Mechanical Advantage = Resistance Force OR Mechanical advantage = Length of force arm

Length of resistance arm

First-class Levers
• Produce balanced movements when axis is midway between force & resistance (i.e. a seesaw)
• Produce speed & range of motion when axis is close to force, (triceps in elbow extension)
• Produce force motion when axis is close to resistance (crowbar)

Second Class Levers
Produces force movements, since a large resistance can be moved by a relatively small force
– Wheelbarrow
– Nutcracker
– Loosening a lug nut
– Raising the body up on the toes

Third-class Levers
• Produce speed & range-of-motion movements
• Most common in human body
• Requires a great deal of force to move even a small resistance
– Paddling a boat
– Shovelling - application of lifting force to a shovel handle with lower hand while upper hand on shovel handle serves as axis of rotation.

Bernoulli Effect

If an object has a curved top and flat bottom (e.g. the wing of an aircraft), the air will have further to travel over the top of the wing than the bottom. For the two airflows to reach the rear of the wing at the same time the air flowing over the top of the wing will have to flow faster resulting in less pressure above the wing (air is thinner) than below it and the aircraft will lift. This is known as the Bernoulli effects.


Methods of Data Collection within Biomechanics include the following;
  • Anthropometric parameters (weight, height, limb lengths, joint markers)
  • Segmental kinematics (stereophotogrammetry, wearable sensors, etc)
  • External forces and moments (dynamometry, baropodometry, etc)
  • Muscular electrical activity (electromyography)
  • Metabolic energy (indirect calorimetry)
  • Simply using Dartfish, VICON an or an app which tracks  

Looking at Biomechanics in Powerlifting specifically the squat with the help of the images; 

We can see some examples of squatting. What we should be trying to do is load the hips/hamstrings more and less anterior sheer force on the knee (don't load the front of the knee, patella tendon/acl). The knee isn't as good as dealing with load when compared to the hip. The hip is much better as it is supported by a lot more muscles than the knee. 

So when we say less anterior sheer force at the knee. What does that really mean? Well first it means limiting the amount of knee flexion (so knees tracking forwards). This will cause damage over the long term. Inexperienced coaches/personal trainers teach their clients inadequate technical demonstration of the lifts (squat) resulting in an increased risk of injury. In the squat that is not using the hips and excessively loading of the quadriceps muscles. This will limit their clients depth to parallel which from studies has the highest EMG activity in the quads but, one of the highest sheer force on the knee joint. 

So to eliminate this, we should try to aim for a near vertical shin when squatting. That way we are taking the load off the knees and recruiting more muscles into the movement such as the hips, glutes and hamstrings. Is there anything wrong with having some knee tracking forward, no, not in the short term however in the long term I believe there will a negative strain put on the joint which may result in injury. 



Now moving on to looking at the analysis of the bar path for 3 different squats. What a coach should remember is that the bar path should remain within a lifters own Base of Support (BOS). When using a weight (external load) this will alter the individuals centre of mass. This will try and force the subject outside their own base of support (BOS). When using weight (external load) it will have an effect on the subject’s perceived centre of mass (PCOM), which is the subject plus the external load. If the PCOM moves outside the BOS, then the squat will become more challenging and difficult. 

If you look at all three pictures they all have different set ups based on the individual limb lengths, previous injuries, strengths/weaknesses etc. However the external load is always over the mid point of their feet. Never tracking too far forward or back. Staying in the middle of the BOS to generate as much force as physically possible. As you can tell as you go from left to right the shin angle becomes more and more vertical in nature as the bar position gets lowered this encourages a more posterior movement which again as I have said before it loads the hips. 

All the power form any athlete comes form their hips and core (core in my eyes is defined as the pec down to the groin). A great way to train the core and hips is by doing box squats. Here is a great review of the exercise by my good friend Jay Farrant; https://www.facebook.com/JayFarrantCoach/posts/1068089763235735 


As a sports scientist (to be) when I am looking at a squat; 

The hip angle for two reasons, one being going below parallel to meet the demands of the sport and two, what is the relation of the hip to knee is it open/closed and or closer/further away from the knee. 
Then I am looking at the knee and  I am asking myself is it vertical, if not why not. What is influencing it. Finally the feet and back angle as this will affect the athletes centre of gravity/torque. But all this can be affected by individual levers.

We have just looked at some heavy terms and meanings within the world of Biomechanics, Here is a presentation myself and some of my fellow students did this year on a Biomechanical Analysis of the Jump Shot in Basketball. With this context it should make it easier to understand. 

At University on my Applied Sport Science course we did a short presentation on looking at

"Can increasing the Knee flexion have a positive effect in the jump shot in Basketball

by Andrew Richardson, Jonny Foulds and Clinton Oduor. 

What we looked at included the following; 

  • Sport of Basketball
  • Importance of a Basketball Jump Shot
  • Basketball Jump Shot: Phase Analysis
  • Basketball Jump Shot: Biomechanical Analysis
  • Comparison of a Jump shot to a Countermovement Jump
  • Does more Knee Flexion encourage a Positive/Negative Result
  • Final Thoughts
  • References


Sport of Basketball

The sport of basketball  contains:
A combination of speed, quickness, power. A lot of energy goes through the knee joints in different movements within the sport e.g. layups, jump shot, rebounding, running, changes of direction. In this presentation the Jump Shot will be looked at.
The jump shot is; A shot with one or both hands in which a player leaps into the air and shoots the ball at the basket at the moment of reaching the highest point of the leap. (Dictionary.com)
Basketball players usually score points during the game using the jump shot (Struzik, Pietraszewski and Zawadzki, 2014) . For this reason, the jump shot is considered to be the most important element of technique in basketball and requires a high level of performance.
Due to it being such a highly used technique this may put added pressure through the knees (Struzik, Pietraszewiski and Zawadzki 2014)


Importance of a Jump shot

Requiring a high level of performance, the jump shot is considered the most important technique in basketball (Struzic, Bogdan & Zawadzki, 2014)
A two legged jump shot consists of more than 70% of an entire basketball game (Struzic, Bogdan & Zawadzki 2014)
Good technique of the Jump Shot means an increase in Jump Shot accuracy which increases the chances of scoring more points.


Basketball Jump Shot: Phase Analysis

There are 3 Phases of the Jump Shot (Babcock 2005)
1. Preparation/Stopping Phase
2. Shooting

  • Fingertip Control
  • Control the Ball
  • Elbow alignment
  • Jump
  • Release
3. Follow Through

Preparation Phase:
When the player is Dribbling the ball towards the basket he will stop with a foot forward called the pivot foot. He cannot move this foot until he performs the shot or pass the ball to another player.



Shooting Phase:
Finger Tip Control; Basketball should be controlled by the finger tips the entire time whereas the palm of the hand does not touch the ball.
Controlling the Ball; The shooting hand controls the ball throughout the entire movement of the shot. The opposite hand should be placed on the side of the ball and sued for balance and control until the shot is released
Elbow Alignment; the elbow in the shooting arm should be close to the body and lined up with the target
Jump; The athlete jumps vertically in the air to perform the shot above the defender hand
Release; The release of the ball should be executed with a full arm extension and a flick of the wrist





Follow Through Phase:
A flick of the wrist and spread of the fingers should follow the final movement of the shot until the ball goes through the net
Following the ball through with the wrist and fingers it’s entire movement will give direction to the ball.



Full Phase Analysis of the Jump Shot




Basketball Jump Shot: Biomechanical Analysis

Below is an image of what the joints (ankle, Knee, Hip, Shoulder and Wrist) are doing during the 3 Phases of the Jump Shot at each specific Phase



Comparison of a Jump shot to a Countermovement Jump: A Valid Testing Measurement


Struzik, A., Bogdan, P. & Zawadzk (2014)
Biomechanical analysis of the jump shot in basketball
20 well trained junior division II basketball players
ground reaction forces measured using A Kistler force plate
Displacements of the upper level of the lower limbs measured with the BTS SMART using passive markers that reflect the emitted infrared radiation (IR).
markers were located at the greater femoral trochanters on both sides of the body.
6 cameras to capture at a frame rate of 120 Hz and 0.2 mm resolution
Subject performed a maximum CMJ without an arm swing (i.e., hands resting on hips) and a jump shot without the ball



Comparison of a Jump shot to a Countermovement Jump: A Valid Testing Measurement 

Aim of this study “A kinematic profile of skills in professional basketball players” 2010, was to compare biomechanical characteristics of lower limbs in the takeoff and landing phases of a counter movement jump without an arm swing and a jumpshot
20 well-trained junior basketball players
Ground reaction forces measure with Kistler force plate
BioWare software used for each leg
Displacements of the upper level of the lower limbs were measured with the BTS SMART system
The system used 6 cameras  to capture at a framerate of 120 Hz
Both movements produced similar curve profiles;
Landing force as twice the take-off force… potentially leading to injury.

Overuse injuries common in basketball
Lower extremity joint kinematics and structural parameters
were collected from 24 players from five professional basketball teams as
they performed manoeuvres typical of their sport.
Jump shot takeoff and jumpshot landing were looked at.
436.9 knee flexion velocity for the jump shot landing and the
layup landing, respectively. The most extreme knee extension was seen in the
jump takeoffs, with the jumpshot takeoff angle averaging -1 degrees, reflecting a completely extended knee.
Maximum knee extension on the jumpshot landing was 9.8 degrees also resulting in a practically straight leg
This could explain why the forces through this movement are so high.
Possibly a softer landing via a better knee flexion on landing



Does more Knee Flexion in a Jump Shot Facilitate a better Performance


Yes and No
For an athlete to generate the most power and force from the jump. He/she must be within their Base of Support (BOS) ie between their feet. If they try and move their weight outside of the midpoint of their own BOS then they will not be able to produce as much force.
By this train of thought having more flexion (per individual) would not increase jump height or a basketball performance. This is due to the increase of load on the knee, increasing the anterior sheer forces which will limit knee and hip extension to carry out a full Jump Shot.
Knee flexion should not exceed similar angles to a CMJ as this will inhibit the power generated from the athlete making him/her rely more on their arms. Which in the sport of basketball you are taught form this position (see image).





Concluding Thoughts

The jump shot is a skill that involves total body movement
All the phases of the jump shot are important for accurate scoring results
A biomechanical analysis can help the athlete improve technique & form of the jump shot
From this it is possible to say the CMJ without an armswing maybe a good measure of the jumping abilities of the basketball players performing the jump shot.
High impact ratios and landing forces suggest the necessity of a greater emphasis on soft landing in basketball. Therefore it is possible that an increase in knee flexion may have a positive effect on the jump shot, not through performance but on injury prevention.


I hope you enjoyed reading this and it has given you a better understanding of what Biomechanics really is and what it entails. 

References


Babcock, R. (2005). Shooting Fundamentals. Retrieved from: www.raptors.com/basketballdevelopment.1-10 [http://www.raptors.com/basketballdevelopment.1-10]
Jump Shot (n.d.) In Dictionary.com online. Retrieved from: http://dictionary.reference
McClay, I. S., Robinson, J. R., Andriacchi, T. P., Frederick, E. C., Gross, T., Martin, P. E., ... & Cavanagh, P. R. (2010). A kinematic profile of skills in professional basketball players. JAB, 10(3).
McGinnis, P.M., (2013). Biomechanics of Sport and Exercise. Champaingn,IL.
Struzik, A., Bogdan, P. & Zawadzk (2014). Biomechanical analysis of the jump shot. Journal of Human Kinetics, 42(1), 73-79.
HAY, J.G. (1993) The Biomechanics of Sports Technique. 4th Ed. London, Prentice-Hall International (UK) Ltd. p. 64-68


Andrew Richardson, Founder of Strength is Never a Weakness Blog





















I have a BSc (Hons) in Applied Sport Science and a Merit in my MSc in Sport and Exercise Science and I passed my PGCE at Teesside University. 
Now I will be commencing my PhD into "Investigating Sedentary Lifestyles of the Tees Valley" this October 2019. 

I am employed by Teesside University Sport and WellBeing Department as a PT/Fitness Instructor.  


My long term goal is to become a Sport Science and/or Sport and Exercise Lecturer. I am also keen to contribute to academia via continued research in a quest for new knowledge.


My most recent publications: 


My passion is for Sport Science which has led to additional interests incorporating Sports Psychology, Body Dysmorphia, AAS, Doping and Strength and Conditioning. 
Within these respective fields, I have a passion for Strength Training, Fitness Testing, Periodisation and Tapering. 
I write for numerous websites across the UK and Ireland including my own blog Strength is Never a Weakness. 
























I had my own business for providing training plans for teams and athletes. 
I was one of the Irish National Coaches for Powerlifting, and have attained two 3rd places at the first World University Championships, 
in Belarus in July 2016.Feel free to email me or call me as I am always looking for the next challenge. 



Contact details below; 

Facebook: Andrew Richardson (search for)

Facebook Page: @StrengthisNeveraWeakness

Twitter: @arichie17 

Instagram: @arichiepowerlifting

Snapchat: @andypowerlifter 

Email: a.s.richardson@tees.ac.uk

Linkedin: https://www.linkedin.com/in/andrew-richardson-b0039278 



Tuesday 15 September 2015

Sprint Training by Holly Clark

Sprint Training by Holly Clark

The 100m sprint is often referred to as the easiest most complicated event in sport. It requires a specific combination of power, speed, flexibility, efficiency and technique. You have to be both aggressive and relaxed at the same time. Getting the balance wrong can be the difference between being world champion and going no further than club representation.

The main aim is to have the best possible strength to weight ratio, allowing maximal force production without carrying too much mass which can reduce movement efficiency.  A lean body mass is desirable to achieve this.

Traditionally, sprinters were short and powerful, allowing for a rapid stride frequency and minimal ground contact time. However more recently sprinters have been becoming taller and increasing their stride length as depicted by Powell's size (190 cm (6 ft. 3) tall, weighing 88 kg (14 stone). He has a stride length of 2.6 meters which allowed him to break Maurice Greene’s WR in 2005 which had stood for 6 years. You can see from the table below how sprinters’ physiques have changed over the years.



Name
PB
Height (cm)
Weight (kg)
Jesse Owens
10.3, 20.7 (1934-1936)
180
75
Carl Lewis
9.86 19.75 (1981-1993)
188
81
Ben Johnson
10.00 (1982-1999)
177
77
Linford Christie
9.87 (1984-1999)
188
92
Michael Johnson
10.09, 19.32 (1991-2000)
185
77
Maurice Greene
9.79 (1997-2004)
176
75
Asafa Powell
9.72 (2002-2015)
190
87
Justin Gatlin
9.74 19.57 (2002-2015)
185
83
Tyson Gay
9.69 19.58 (2005-2015)
180
77
Usain Bolt
9.58 19.19 (2004-2015)
196
94
Jason Smyth T13/12
10.22 20.94 (2005-2015)
177
72
Jonnie Peacock T44
10.48 (2006-2015)
178
73

Technique
When Michael Johnson was competing he was as near to the full marks model of sprinting as you could possibly get. He was so efficient when competing that it allowed him to be the first man to win Olympic Gold and set world records in both the 200m and 400m. Now when he is commentating he always mentions an athlete’s form and how it could be improved.
The key points of good technique are outlined below:

  •          Driving out at a 450 angle is most effective to get to top speed quickly
  •          Head – straight forward and no lateral movement to maintain balance and technique
  •          Arms – should be driving hard. Hand should rise no higher than the shoulder elbow bent at less than 900. They should have no lateral movement as this will affect legs. Hands should be relaxed if closed to avoid causing tension. Shoulders should be down and relaxed
  •          Core - steady holding body straight and allowing the most efficient transfer of forces through the hips
  •          Legs – straight leg drive and high knee lift with no lateral movement. Knees should come high to allow increased stride length. Commonly see knees coming across the body which takes more time. Driving the ankle up the side of calf then out allows more force
  •          Ankle dorsi-flexed pre plantar flexion to increase propulsion     
  •          Keeping the muscles relaxed and not tensing up will help maintain good technique and reduce likelihood of injuries







Stride length v cadence
There has been much debate about whether to improve your speed you should increase your stride length or stride frequency. A study conducted by A J Murphy et al (2003) on the key determinants on acceleration have found that for early acceleration, participants had quicker times with reduce foot contact time and higher stride frequency. Over shorter distances, and particularly for games sports, it is therefore desirable to have high cadence to achieve maximal acceleration. The table below shows that over the first 30m, during acceleration, Bolt’s split times are no faster than the other athletes. Beyond this point however, when reaching maximal speed, Bolt’s stride length gives him the advantage. It takes him 41 strides to run 100m compared to Dwaine Chambers who takes 43 or 44. Bolt’s stride length is on average 20cm longer than the rest of the field according to research conducted by Maćkała Krzysztof and Antti Mero (2013).

Therefore, it is advantages to have higher cadence in the early stages of a race to accelerate quickly but beyond this point a longer stride length is more advantageous.


Ben ‘88
Carl ‘88
Asafa ‘05
Bolt ‘08
RT
0.132
0.136
0.104
0.165
0-10m
1.83
1.89
1.89
1.85
10-20m
1.04
1.07
1.02
1.02
20-30m
0.93
0.94
0.92
0.91
30-40m
0.86
0.89
0.86
0.87
40-50m
0.84
0.86
0.85
0.85
50-60m
0.83
0.83
0.85
0.82
60-70m
0.84
0.85
0.84
0.82
70-80m
0.85
0.85
0.84
0.82
80-90m
0.87
0.86
0.85
0.83
90-100m
0.9
0.88
0.85
0.9
Time
9.79
9.92
9.77
9.69

Warmup
Needed with every sport.
What you do should be kept consistent so that when you come to competition you know what you are doing and help reduce any anxiety. For most sprinters a warm up can take from 15-25 minutes depending on the weather conditions and how they are feeling.

You may follow standard RAMP (Raise, Activate, Mobilise, Prepare) procedure or be adapted to a Dynamic movement circuit completed over 20-30m.

You should focus on technique when completing the drills as they help to develop muscle memory through rewiring the CNS (Central nervous system) to make it fire faster and more effectively which benefits you in both training and races.  Drills may seem simple and boring but if done properly can really enhance your technique, posture and overall performance. 

Resisted Sprints
Hills and using sleds are forms of resisted sprint training. They are brilliant ways to develop muscular strength, drive phase, power and technique. They will also improve your resilience as they are hard work and often a stomach emptier!

A study conducted on Rugby players by Harrison, Andrew Burke and Gillian in the Journal of Strength and Conditioning found that using sleds significantly decreased the time taken to complete the first 5m of a 30m sprint, showing the benefits for a sprint start.

Having a good arm drive is extremely important for hill training, as the more you drive your arms, the more your knees are encouraged to lift, increasing stride length, which you need to get up the hill.
Using a trail hill where the surface underneath is unsteady will also provide additional strength to the muscles and tendons of the ankle and thus help reduce the likelihood of any injuries.

The length of the hill should be relative to the distance that you are training for.  For up to 200m the hill shouldn’t take you longer than 60seconds to complete depending on the gradient. The steeper the hill the more powerful you are required to be.

An example session would be 8x45s steep hill with a walk/jog down recovery. Controlling this recovery time is essential; 90seconds to 2minutes is more than adequate for this session.
To improve endurance you should reduce recovery time and ensure that you jog down. For more powerful sessions, rest for up to 4 minutes between each rep.



Intervals
Fast interval training is a signature part of any sprint program. Known by many as HIIT training, the benefits spread to all sports and those who just want to keep fit. The times and distances vary throughout the season. Winter training to develop speed endurance would include 8x60s:60s or 2x4x200m 2min rep recovery and 5 min set recovery. Pure speed work would be a lot shorter with longer recover such as 3x3x60m 3min rep recovery 5 min set recovery. Typically 2 sessions will be completed a week alongside 1 resisted sprint session and a circuit session.

Strength training
A good weights programme is needed to help optimise an athlete’s performance. For sprinters this will commonly include Olympic lifts such as cleans, squats, deadlifts, walking lunges and step-ups. Single leg work and exercises for foot strength are also necessary to help reduce the likelihood of injury.

A study conducted by U Wisloff et al in the British Journal of Sports Medicine (2004) has found strong correlation between maximal strength in half squats (900 knee angle) and sprint performance and jump height and concluded that the maximal strength squat determined sprint performance. This therefore gives reason to be performing squats and developing maximal leg strength in the gym to improve 30m sprint time.

Upper body strength work should also be in the program to improve arm drive, however this must not be done in excess as this can give unnecessary muscle mass to carry. For example doing 30 second arm drive sprints holding light weights is a great way to build the dynamic strength needed to race.
Core strength is really important. Having a strong core allows forces to be transferred through the body most efficiently. It also avoids any unwanted rotations or movements which would both waste energy and reduce streamlines.

Key part is also plyometric training. These prepare the body for the powerful sprint start and for ground contact. Reducing ground contact time is important for speed. Care must be taken especially if you have a history of bad shins or ankles.

Circuit training
As part of my training I use individual load circuit training once a week, usually 3x30:10s W:R with 12-16 stations. The circuit is for general conditioning although I also use it focus on technique and areas that I find are weak.

Recovery
Very important and necessary for improvements in performance to occur! It is often said that “rest is not a four letter word” and as with many sports, people may find it requires more discipline to rest than to do their sessions due to their competitive nature. Rest must be specific! Water and nutrition intake must also be maintained.

Periodisation
The traditional Matveyev model for sprint training is a Long to short program where the athlete performs slower aerobic work and anaerobic work at the beginning of the training year to build endurance and strength and then progresses to faster anaerobic work towards competition.
The other model put forward by Coach Charlie Francis is the Short to long approach where you do more speed work in the winter and gradually increase the distance.
There is not a one size fits all, you need to find the training that works best for you. Personally I have found for myself that the long to short suits me better as the HIIT training involved offers more calorie burn and helps keep me lean. From speaking to other female athletes they have had a similar experience. The short to long method in my opinion is more suited to the highly trained and for those only competing in 60m and 100m sprints or is your first sprint training program.

Other sports
Michael Jonson has set up MJ Performance (MJP) which assists professionals and junior sports people improve their speed, strength, suppleness, stamina and skill which compliments the technical work they do in other sports. The Global Performance director has justified the use of their program saying that “98% of what happens on a football pitch is without the ball…it is very uncommon for any player to have the ball at their feet for more than two minutes”. This has been recognised by several clubs including Manchester United, Arsenal and FC Dallas.

Football:
Adam Gemili of GB competed in the 100m at the 2012 World Junior Championships in Athletics in Barcelona getting winning time of 10.05s: a new championship record. He is a former football player (defence) for league 2 side Dagenham & Redbridge having spent seven years in the youth academy at Chelsea from the age of 8. In 2012 he decided to focus fully on athletics.
Bolt spent his time as a child playing cricket and football and it was his high school cricket coach who noticed his speed on the pitch and urged him to try track and field events. He also did a training session with Cristiano Ronaldo in 2009 to help him with his sprinting technique.

American Football:
Gatlin reportedly planned to serve his four-year ban playing American football. ESPN reported in November 2006 that he had worked out with the Houston Texans, despite his little football experience. In May 2007 The Tampa Bay Buccaneers announced that Gatlin was one of 28 free agents taken to their 2007 rookie camp on tryout contracts. He tried out for the team as a wide receiver although was unsuccessful.

Rugby Union:
Carl Isles was ranked 36th fastest sprinter in the US in 2012 (10.24). He has since changed to rugby Union 7s and has since been dubbed “Fastest man in American Rugby” (Rugby Mag). He now plays for Glasgow Warriors. Similarly English Schools’ champion: sprinter Tyrese Johnson-Fisher has followed in a similar path reaching the NatWest Vase rugby final with his school, despite clocking 10.91 seconds for the 100m, the fastest ever time for a boy of his age in Britain (Sport 360).

Rugby League:
Studies conducted showed that the majority (67.5%) of sprints completed during a rugby league game were over <20m, and 78.7% of sprints were done without the ball. This suggests that players could benefit from doing technique work to improve their efficiency. Also they benefit more from acceleration work due to the nature of the distance usually sprinted. (Sprinting patterns of National Rugby League Competition Gabbat, Tim J)
  
Why you should sprint
Having innate speed and acceleration gives you a great advantage in many games sports. Sprint training helps to benefit this by improving technique and thus your efficiency.
Sprint training methods have also been recognised for their health benefits with the likes of HIIT training becoming a common method used by many now.



References
-          Gabbet, Tim J Sprinting Patterns of National Rugby league Competition 2012
-          U Wisloff, C Castagna, J Helgerud, R Jones, J Hoff Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players 2004
-          Aron J Murphy, Robert G Lockie and Asron J Coutts Kinematic Determinants of early acceleration in field sport athletes 2003
-          Harrison, Andrew J; Bourke, Gillian The effect of resisted sprint training on speed and strength performance in male rugby players
-          Maćkała Krzysztof and Antti Mero A Kinematics Analysis Of Three Best 100 M Performances Ever 2013


If you wish to contact Holly about Sprint Training please use her email below;
hollyc.94@hotmail.co.uk

Andrew Richardson, Founder of Strength is Never a Weakness Blog





















I have a BSc (Hons) in Applied Sport Science and a Merit in my MSc in Sport and Exercise Science and I passed my PGCE at Teesside University. 
Now I will be commencing my PhD into "Investigating Sedentary Lifestyles of the Tees Valley" this October 2019. 

I am employed by Teesside University Sport and WellBeing Department as a PT/Fitness Instructor.  


My long term goal is to become a Sport Science and/or Sport and Exercise Lecturer. I am also keen to contribute to academia via continued research in a quest for new knowledge.


My most recent publications: 


My passion is for Sport Science which has led to additional interests incorporating Sports Psychology, Body Dysmorphia, AAS, Doping and Strength and Conditioning. 
Within these respective fields, I have a passion for Strength Training, Fitness Testing, Periodisation and Tapering. 
I write for numerous websites across the UK and Ireland including my own blog Strength is Never a Weakness. 
























I had my own business for providing training plans for teams and athletes. 
I was one of the Irish National Coaches for Powerlifting, and have attained two 3rd places at the first World University Championships, 
in Belarus in July 2016.Feel free to email me or call me as I am always looking for the next challenge. 



Contact details below; 

Facebook: Andrew Richardson (search for)

Facebook Page: @StrengthisNeveraWeakness

Twitter: @arichie17 

Instagram: @arichiepowerlifting

Snapchat: @andypowerlifter 

Email: a.s.richardson@tees.ac.uk

Linkedin: https://www.linkedin.com/in/andrew-richardson-b0039278