- Re-activating and strengthening the gluteal muscles
- Shoulder instability and rotator cuff issues
- Training for power and speed
- Exercise groups in-depth
- Core training part I: Inner and outer unit
- Effective and safe supplements
- Planes of motion
- Core training part II: a functional approach
- Prevention and rehabilitation of hamstring injuries
- Knee flexion exercises - friend or foe?
Training for power and speed
By Bram Swinnen
Success in most sports depends on the level of power and speed the athlete can exert.
With beginners resistance training can improve both strength and power as a result of hypertrophy and neural adaptations. An improvement in strength results in an increase of power. With advanced athletes however resistance training does not result in simultaneous improvement in strength and power . Trained athletes require more specific training interventions to further improve power output .
Resistance training is only half of the equation (Power = force x velocity). Zatiorsky states that it takes 0,4 seconds to achieve maximal muscle force . During sport actions time is limited however. The athlete has to exert as much force as possible in a short period of time. Compare the 0,4 seconds necessary to achieve peak force to the 0,07 second ground contact time of Tyson Gay while sprinting and you will understand that strength gains do not necessarily transfer to faster sprinting .
|Sprint running||0,08 – 0,10|
|Long jump||0,11 – 0,12|
|High jump||0,17 – 0,18|
|Javelin||0,16 – 0,18|
|Shot put||0,15 – 0,18|
|Horse vault (gymnastics)||0,18 – 0,21|
Low speed - high force resistance training will only raise one end of the strength-velocity curve and is not enough to improve explosiveness and speed of movement. There is no connection between the ability to generate great force and the ability to realise it at maximum speed .
The SAID principle (Specific Adaptations to Imposed Demands) also applies to speed. Training with a specific load and thus velocity results in velocity-specific increases in muscle activation [8, 9, 10]. The adaptations to the nervous system in response to power training differ from the changes seen with training to increase muscle strength . Power training results in high-frequency motor unit activation and the selective recruitment and synchronisation of the high-threshold motor units [11, 12, 13]. The increased neural activation of the muscles, the improved interaction between synergists and decreased co-contraction of antagonists contributes to athletic performance enhancement [14, 15].
To maximally increase power and performance different resistances that span the force-velocity curve have to be incorporated into the training, so athletes present their neuromuscular systems with a variety of different stimuli.
Heavy resistance training to enhance maximum strength
The use of heavy resistance training is theoretically based on the size principle [16, 17], which states that motor units are recruited in an orderly manner from the smaller (lower threshold) to the larger (higher threshold) motor units. The low-threshold motor units are predominantly composed of slow-twitch fibres, which are well suited for low-intensity, long-duration activities. The high-threshold motor units consist of a large number of fast-twitch fibres, which produce more power output than slow-twitch motor units and are responsible for athletic performance [18, 19]. The high-threshold fast-twitch motor units will be recruited as the force required increases [2, 8, 19, 20].
Maximum strength (low speed - high force) is a contributing factor to explosive power. All explosive movements start from zero or slow velocities, and it is at this acceleration phase of the movement that slow-velocity strength can contribute to power development. At the higher velocity component of the movement, however, slow-velocity strength capacity has a reduced impact on the ability to produce high force [30, 31, 32]. Training to enhance leg strength has excellent transference to agility and vertical jump performance, but considerably less to sprinting performance [33, 34].
Training to enhance leg strength has excellent transfer to vertical jump performance.
The longer the contact time, the longer the time that force can be exerted and the higher the performance benefit that can be expected from enhanced strength. The time to apply force during most athletic movements is around 0.1 to 0.2 seconds however. The rate of force development (RFD) – the ability of the neuromuscular system to produce the greatest possible force in the shortest possible time – determines success in most sports and should be a major focus of training.
Research shows that the force output during heavy lifting increases when the load is increased. Second, as the load increases, the velocity of the lift decreases with a greater factor than the force increases. Third, since power equals force times speed, the loads that lead to the highest power output are 30%-40% of 1RM [2, 32, 35].
Force-velocity curve and peak power output
Force-velocity curve and peak power output.
Zatiorsky states that lifting above 90% of your 1RM leads to very slow bar speeds and low power outputs. Loads of 90% of 1RM and below are better suited to enhance the RFD . This is in accordance with L.S. Dvorkin, who carried out research with weightlifters of all qualifications over a prolonged period of time to determine the effect of training load. He concluded that all levels of lifters made the highest gains in back squat strength with 3–4 reps/set at 70-80% of 1RM . Also the Sheiko method, a multi-year training plan developed by Boris Sheiko (coach of the Russian powerlifting team since the 1990s) that can take a powerlifter from novice to elite, requires lifting loads that range most of the time between 70 and 80% of 1RM. Explosively lifting loads of 70%-80% of 1RM with perfect technique and no sticking point results in the highest gains in 1RM loads, especially in the medium and long term .
It is generally accepted that when training to enhance speed and power, quality should be stressed at all times. Like power and speed, strength is also a consequence of efficient neuromuscular processes. The effectiveness of a program to increase strength is also related to the quality of each repetition. Grinding out repetitions at very slow speed for the sake of quantity not only compromises speed and power performance, but will also result in decreased strength gains .
Alexander Prilepin, the best weightlifting coach of all times and sports scientist, designed a table based on studying training logs of more than thousands weightlifting champions of all categories. His table gives recommendations about the optimal number of reps that should be performed within each intensity zone. If you follow the table you should be able to maintain good bar speed and maximise strength and power development.
|Intensity: % 1RM||Rep range||Reps total||Optimal reps|
|<70%||3 – 6||18 – 30||24|
|70-79%||3 – 6||12 – 24||18|
|80-89%||2 – 4||10 – 20||15|
|>89%||1 – 2||4 – 10||7|
Prilepin’s table for optimal strength and power development
Rate of force development and ballistic training
During the vast majority of sport actions time is limited and the athlete does not have the time to produce maximal force. Not the strongest athletes, but those that can produce the greatest force in the shortest time have an advantage. To reach higher forces and velocities during fast movement, training should focus on improving RFD. While heavy resistance training increases the highest point of the force-velocity curve, RFD training improves the slope of the curve [8, 32, 33, 37, 38]. An increase in RFD allows reaching a higher level of muscle force in the early phase of muscle contraction.
Effects of jumping and heavy weight training on Maximal Strength (PF) and Rate of Force Development (RFD).
Several studies have shown that to enhance maximal power, athletes should train with the velocity and resistance that maximises mechanical power output [2, 8, 39]. In single-joint movements maximal power is produced at 30% of 1RM. Speed repetitions performed with 30% of 1RM will not improve the RFD however . Newton and co-workers  demonstrated that when 45% of 1RM was lifted as explosively as possible, power decreased significantly during the final half of the range of motion (ROM), The reduction in power is due to activation of the antagonist muscles and lack of agonist neural activation, in order to decelerate the bar and reach zero velocity at the end of the movement [39, 40]. Deceleration accounts for 24% of the movement with a heavy weight and 52% of the movement with a light weight .
With the use of ballistic movements, movements in which the weight can be released, power and acceleration are enhanced throughout the entire ROM . Jump squat and bench throws are therefore far superior to speed reps for power development . Speed reps merely train the neuromuscular system to decelerate the movement towards the end of the ROM and are therefore counterproductive. Ballistic exercises, Olympic lifts and plyometrics allow the athlete to accelerate throughout the entire ROM.
Explosive movements do not adhere to the size principle. During high-velocity movements and high-power outputs high-threshold motor units, which are composed of a large number of fast-twitch fibres, are recruited first . The low-threshold motor units, which mainly consist of the smaller slow-twitch fibres, are skipped over to facilitate power production. Part of the training effect from ballistic training is the enhanced ability to activate the highest-threshold motor units .
Many studies have shown that with Olympic lifting exercises the highest amount of power can be produced of all human movement [43, 44, 45]. The snatch and clean & jerk exhibit power outputs far greater than those of the squat and deadlift .
Because of the potential of these lifts to produce high-power outputs and their movement- and velocity- specificities to many sport activities (e.g., jumping, running, throwing), Olympic lifts are considered as some of the best training exercises to maximise athletic performance [43, 44, 45] . This is illustrated by studies done at the Montreal and Barcelona Olympic games, which showed that the Olympic weightlifters outperformed all other groups of athletes in the vertical jump.
Many strength and conditioning programs incorporate weightlifting exercises for their athletes. For example, most of the strength and conditioning coaches in the National Football League (88%), National Basketball Association (95%), and National Hockey League (100%) report using Olympic lifts in their programs [46, 47, 48].
Load specifity to enhance power performance
In analogy of a car, heavy resistance training will enhance the engine capacity, while RFD training maximises the engine power. To improve the RFD ballistic exercises in which the weight can be accelerated over the entire ROM, are superior over speed reps without propelling the bar into the air. Remains to be determined the training load of these ballistic exercises to optimally enhance power output. Some authors recommend training with the load that produces maximal power output, because this results in the greatest increase in power and force over the entire velocity range of the curve [2, 32, 49]. The peak power output is typically seen with lifting loads of 30% of 1RM, but might vary between upper and lower body and may depend on the exercise and experience of the athlete [2, 24, 25, 32, 35, 49]. Monotonous power training however, in which one load is prescribed is not recommended. Training monotony does not optimally enhance performance and increases the likelihood of overtraining .
Several studies also demonstrate that training adaptations are velocity specific. Training adaptations are greatest at or near the training velocity [8, 9, 10, 32]. Training with heavy resistance results in the greatest increase in power at low speed - high force movements, while ballistic training with low loads produces the greatest increase in unloaded movement velocity [8, 9, 32]. To maximally increase power performance different loads that span the entire force-velocity curve have to be incorporated into the training. Most sports also involve motor skills that cover the entire force-velocity curve.
Verkhoshansky made a distinction between speed-strength and strength-speed . These are separate training modalities that pertain to defined areas of the force-velocity curve and both need to be addressed to maximise power.
Different modalities of force-velocity curve
Different modalities of force-velocity curve.
To improve each modality and each part of the speed-strength spectrum, there is an appropriate choice of exercises. Plyometrics and sprints are performed with high movement speeds and the total force production is lower because there is no additional external load. This places plyometrics and sprints more towards the speed end of the spectrum. Maximal peak power outputs for the jump squat are seen with loads between 10% and 45% of 1RM [2, 32, 3]. Performing jump squats with these loads will therefore result in the greatest increase in speed-strength. The optimal load to maximise power outputs in Olympic lifts are higher compared with the jump squat. Maximum power outputs in Olympic lifts occur between 60% and 80% of 1RM and are therefore perfect to develop strength-speed [33, 45, 53, 54].
Olympic lifts are perfect to develop strength-speed.
Jump squats are far from ideal to develop the strength-speed modality for two reasons. First, jump squats with a load above 60% of 1RM pose safety concerns because of the high impact forces on landing. Second, the optimal loads to maximise power outputs in the jump squat appear to be lower [2, 32]. Some authors see jump squats as the perfect replacement for the technically more complex Olympic lifts. This is a misconception however, because jump squats and Olympic lifts perfectly complement each other to maximise power and speed.
Because strength is a prerequisite of power, the athlete should progress from strength training to power training in a logical sequence. Bompa and Carrera note that power is developed in two stages. The first stage involves the recruitment of fast-twitch fibres through heavy resistance training based on the size principle. The second stage involves an increased firing rate and synchronisation of these high-threshold fast-twitch motor units through ballistics . Periodization to maximise power performance suggest a training emphasis for either strength or power and does not suggest either should be trained in isolation. The increases in power and motor performance with combined strength and plyometric training are greater then with either training method alone [56, 57]. Research also supports the superiority of concurrent heavy resistance training/ballistics [8, 19], heavy resistance training/sports-specific task [58, 59] and ballistics/sports-specific task .
Russian complex and Post Activation Potentiation
Verkhoshansky states that resistance training programs which incorporate plyometrics are superior to those that do not include plyometrics.
In the Russian complex a set of heavy resistance training is followed by a set of a biomechanically similar plyometric exercise. Lifting a heavy load will enhance the power output in the subsequent set of plyometrics [60, 61]. The enhanced explosiveness has been attributed to the post-activation potentiation (PAP) phenomenon. Performing a near-maximal contraction before the unresisted drill stimulates the central nervous system, which results in enhanced high-threshold motor unit recruitment [60, 61]. The increased amount of recruited fast-twitch muscle fibres as a result of lifting the heavy load will carry over to the subsequent unresisted explosive exercise. This enables the athlete to move faster, more explosive .
On the cellular level, Post-Activation Potentiation enhances the sensitivity and the binding rate of the contractile proteins (actin and myosin), which means faster muscle contractions (increased myosin light-chain phosphorylation) [61, 63, 64].
|Front squat||4 reps @ 80%||3’|
|Hurdle jump (multiple response)||6 – 8 reps||2’|
Example of Russian complex: perform this combination for 3-4 sets
The Bulgarian method starts with a high intensity exercise, followed by progressively working down to a plyometric exercise. In one workout all the modalities of the force-velocity curve are addressed: maximum strength, strength-speed, speed-strength and speed.
Ivan Abadjiev is the founder of the Bulgarian method. He skyrocketed a small country like Bulgaria into weightlifting stardom and kept it there for decades. It is a hardcore training routine that was only possible with hardcore recovery methods: steroids (called recovery agents by Abadjiev), ice baths, massages, etc. The system has major downsides, but a part that is very useful for power production are the flushing sets at various intensity after attempting a maximum.
|Front squat||3 reps @ 85%||3’|
|Power clean||4 reps @ 75%||3’|
|Jump squat||5 reps @ 30%||3’|
|Hurdle jump(multiple response)||6 – 8 reps||3’-4’|
Example of Bulgarian method: Start with heavy resistance exercise and progressively work down to plyometric exercise. Repeat 3 to 4 times.
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