Thursday, 10 March 2016

Acceleration vs Max Speed

I was posed this question ‘ Which is more important to improve, acceleration or maximum speed in sprinting’? The original question was for the 200m but for the sake of this post I will keep it broad.

Well the answer, as you may well have figured is ‘it depends’. Certainly there is a plethora of factors that will influence all races and many intrinsic and extrinsic factors impacting each athlete but for the sake of argument lets assume that our athletes are in a vacuum with minimal influence from outside and our actions will have a direct effect on the outcome.


Before we start we need to discuss the math of speed and acceleration. Speed relates to how quickly the athlete moves. This is done by dividing ‘how quickly’ by ‘how far’. This is important to not to confuse this with velocity, which also includes the resultant direction. This is not important in the 100m as the speed and velocity would be the same but they would be significantly different over the 200m.

Speed = Distance/Time
Velocity = Displacement/Time

Acceleration is the rate of change of velocity. Velocity is measured in meters per second while acceleration is measured in metres per second per second. To determine actual rates of acceleration, instantaneous speed is required i.e. the speed at the 10m mark.

Acceleration = Velocity/Time
m/s to km/h is m per s/1000 x 3600
km/h to m/s is km per h x 1000/3600

But who will run the faster 200m?

These models are hypothetical and to be accurate a coach will need to insert their athlete’s times. But let us assume for a moment that the 200m is divided in to a acceleration phase (0 – 50m), a maximum speed phase (50 – 150m) and a deceleration phase (150 – 200m). We also have the average speed and the total time.

Race phase
Actual time (s)
Acceleration
- 3%
Max speed
- 3%
Deceleration
- 3%
Acceleration (0-50m)
5.90
5.72
5.90
5.90
Max Speed (50-150m)
9.70
9.70
9.41
9.70
Deceleration (150-200m)
5.30
5.30
5.30
5.14
Average speed (m/s)
9.60
9.65
9.70
9.64
Total time (s)
20.90
20.72
20.61
20.74



Therefore if we improve each factor by a 3% margin there is a more profound effect on the average speed with the adjusted maximum speed and therefore the total time in this example. So the answer to this question: the athlete who improves their average speed the most will run faster and in this example this is achieved through improving maximum speed. 

In reality this does not happen but it is a nice controlled experiment to see effect. The goal for any coach is to maximize their athletes potential and try to not waste valuable time and energy on inefficient gains. In this example the coach may choose to focus their athletes time on speed endurance and less time on pure speed training however if the distance were changed to 60m then the most likely way to effect average speed would be to improve on the acceleration. Conversely the 400m coach may heavily focus their attention on maximum speed as an improvement in the acceleration phase would have even less improvement than the 200m example. 





Wednesday, 9 March 2016

High Kick to Sprinter’s Lunge

The high kick to sprinters lunge is a dynamic multijoint exercise that can be used as part of a dynamic warmup, provide an active stretch for the lower extremities or to improve hip mobility. This exercise is ideal for sprinters as it activates the anterior muscles of the leg while providing a stretch for the posterior muscles during the kick phase. The reverse lunge provides a dynamic hip flexor, glutes and hamstring stretch. 

Muscles
Iliopsoas, rectus femoris, sartorius, and tensor fasciae latae, hamstrings and gluteus maximus, rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis

Benefits
Although both exercise are often used individually during a dynamic warmup by combining them a component of proprioceptive control is introduced. This coupled with similar movement patterns in sprinting may provide a higher level of specificity and dynamic muscle overload to effectively prepare for training, racing or weights. 

Exercise initiation 
Begin standing in a neutral position feet hip width apart. Remember in its simplest form sprinting is a sagittal movement. This exercise mimics this and requires the athlete to avoid any deviation laterally during the lunge. There is however some truck rotation to activate the internal and external obliques. 

Start position

Action
Initial the exercise with a step forward to preload for the trail leg to come through. Kick the trail leg forward while reaching across with the opposite arm towards the foot. Following the high kick the athlete immediately drops into an exaggerated reverse lunge.  The leg posterior has a hip Angle of at least 180'and 90' at the hip knee and ankle of the anterior leg. The athlete holds this position for a moment before returning to the start position. 

Preloading

High Kick

Reverse Lunge

Sets and reps
Beginner: 1 set of 3 reps. The exercise can be broken down in to its components until balance and coordination has been improved. 
Intermediate: 2sets of 3 - 5 reps
Advanced: 2 - 3 sets of 5 - 10 reps

My opinion
This exercise contained all the components needed in a good dynamic exercise. It could also be argued that it saves time by combining 2 exercises into one. My personal preference in my warm up, have tried it for a few days is that I prefer to perform the high kick and lunge separately. I like to focus on the individual actions of high kick and lunge and I feel that each one is important enough to warrant Its own exercises. In saying that I can't fault the exercise in any way and is useful to add to an extended programme. 

Walker, M. Strength and conditioning. (2013). Volume 35, number 5. 



Tuesday, 8 March 2016

Nike Zoom Superfly R4 Running Spike - 2016

'I have no affiliation or personal relationship with Nike. All opinions are my own'.

The Nike Zoom Superfly R4 Track Spike is an ultralight spike made for the power sprinter.  Typically the tool for the short sprints and hurdles the spike features controlled lockdown across its top and a powerful spiked plate for traction and propulsion.



The upper used Flywire cables to create a glove like fit by clamping down the foot creating a secure confident lock while a thin Phylon midsole wedge provides lightweight, low-profile impact cushioning. The rigid outer Pebax® plate provides feedback and delivers potential energy into every stride.
This shoe is for the elite sprinter. Updated from its predecessor for the experienced the Nike Zoom Superfly R4 Running Spike is designed for the athlete who wants a dynamic, locked down fit with an aggressive plate that offers stability without increasing bulk.









Monday, 7 March 2016

Pull from the Knee

'There is no doubt that track athletes require weight training to optimise their performance. However weight training can be a daunting playground especially with the plethora of information out there confusing the issue. Weight training is time consuming and many exercises are moderately effective or ineffective in improving a sprinters ability. The formula is simple; will this exercise make me faster? Of course this question is not that simple but for the sake of this argument lets assume this is true. What must an exercise be? Firstly it must be specific. It must mimic the movements of sprinting. Secondly, it must overload the active system and thirdly, it must be progressive'.  

Pull from the Knee (PfK)

This exercise effectively breaks down the components of the clean and jerk (C&J) and snatch emphasizing the triple extension of the hips, knees and ankles. Weightlifting exercises such as the C&J and snatch are regarded as superior training methods for athletes in power-based sports. Due to the explosive nature of these exercises it is important for athletes follow clear guidelines of form and safety while performing such exercises to prevent injuries. The pull from the knee can acts as a teaching progression for these exercises as well as a useful exercise in its own right.

Muscles involved

Erector spinae, rectus abdominus and obliques, subscapularis, latissimus dorsi, brachioradialis, trapezius, splenius capitis, splenius cervicis, infraspinatus, serratus posterior inferior, rhomboid major, rhomboid minor, and the supraspinatus. Also active during the movement phase, levator scapulae, teresminor, teresmajor, rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius, gluteus maximus, biceps femurs, semimembranosus, and semitendinosus, gastrocnemius, soles, tibialis posterior, flexor digitorum, peroneus longus, and the peroneus brevis.

Benefits of the exercise
  • Maximum transference to sprinting through transition to peak power position and acceleration of an external load using triple extension. 
  • The PfK reduces of stresses from moving the load from the floor to the second pull. 
  • High rates of force and power production are required to accelerate the load from at static position. 
  • The pull from the knee is less complex than the C&J and snatch thus effectively reducing the risk of injury.


Start position
The weight should be positioned on boxes or squat rack at the appropriate patella height. Feet hip width apart with hands (hook grip) placed in the C&J position. Flex forward at the hips while aiming to maintain a normal curve in the lower back. Slightly bend the knees positioning the shoulders ahead of the bar.

Start position

Transition
Inhale deeply while tightening the muscles in the torso. The athlete should initiate the exercise by engaging their hamstrings, glutes, and erector spinae muscles to begin to move to the bar upwards. The peak power position is accomplished by extending their back while forcing the hips and knees forward at the same time. The bar should be moving vertically as close to but not touching the body.

Transition Power position


Second pull
From the power position the athlete uses the momentum from the initial pull to initiate the triple extension. As the bar brushes the thighs the athletes explodes through the hips, knees and ankles while shrugging their shoulders to maximize the loads velocity. At this point the athlete can lower the bar to prepare for the next repetition.

Second pull

Loading
Dependent on the periodisation the PfK can be used with higher reps during strength endurance training block with light to moderate loads (2 – 5 reps at 80 -100% of Power clean) . During the strength-power training block use increased loads and reduced volume (1 – 3 reps at 120 – 140% of Power clean). Explosive speed and maintenance block use reduced volume and intensity to enhance power output (4- 6 reps at 40 – 60% of Power clean). 

However, the loads prescribed should be based on the athlete’s ability and strength. Weaker or less technically proficient athletes should focus on improving peak power through lighter loads, whereas heavier loads may be prescribed for a stronger, more technically proficient athlete.

Pull from the knee: Proper Technique and Application, DeWeese, et al, (2016)
Strength and Conditioning Journal, Volume 38, Number 1.

Sunday, 6 March 2016

Adidas Spikes for 2016 (Adidas Adizero Prime SP Running Spikes)

I have no affiliation or personal relationship with Adidas. All opinions are my own.

Adidas Adizero Prime SP Running Spikes

The Adidas Adizero Prime SP Spikes are one of the lightest track spikes available. They deliver superb returns from each stride while keeping the foot in place to generate greater forward propulsion.


Weighing just 96g, this spike facilitated optimal performance for the elite athlete. The synthetic upper works in conjunction with the Sprint plate to prevent lateral foot motion while allowing optimum forward propulsion on the straights and curves.




The adiZERO Nano Plate enhances the potential energy from each stride transferring the power through the foot while reducing the torque across the mid-foot. This provides a greater energy return, propelling you forwards.

This shoe is the elite sprinters choice. Developed for the experienced athletes who desire precise feedback while sprinting. For short sprints and hurdles