Elements of a Strength Training Program
Hypertrophy
Synonymous with
most people’s perception of strength training, hypertrophy refers to increased muscle bulk and size. This is only one
aspect of a sport-specific strength training program and one that should be included for only a select group of athletes.
Football and rugby players require significant bulk to withstand very aggressive body contact. For most athletes however,
too much muscle bulk is a hindrance. And remember that a larger muscle is not necessarily a stronger muscle.
Maximal Strength
Maximal strength
is the highest level of force an athlete can possibly generate. Its importance will vary between sports but this relates more
to the length of the maximal strength training phase than whether it should be included or not (1). The greater an athlete’s
maximal strength to begin with, the more of it can be converted into sport-specific strength endurance or explosive power.
Maximal strength
training can improve exercise economy and endurance performance (2,3). Interestingly, it does not appear to lead to a significant
increase in muscle hypertrophy (4).
Explosive Power
Rarely is an
athlete required to produce a singular maximal effort in their sport. With the exception of powerlifting, most sports require
movements that are much more rapid and demand a higher power output than is generated during maximal lifts (5,6). So while
maximal strength training lays an important foundation increasing the potential for additional power development, if there
is no conversion of this strength into sport-specific power, the program as a whole is much less effective.
An athlete can
be exceptionally strong but lack substantial power due to an inability to contract muscle quickly. Power training is used
to improve the rate of force production and a range of methods such as plyometrics can be employed to convert maximal strength
into explosive power.
Strength Endurance
Explosive power
is not always the predominant goal of the strength training program. For events such as distance running, cycling, swimming
and rowing, strength endurance is a major limiting factor. Again, the greater amount of starting maximal strength, the more
of it can be maintained for a prolonged period.
Strength endurance
can be developed through circuit training or the use of low weights and high repetitions. However, many strength endurance
programs are inadequate for endurance-based sports - a set of 15-20 repetitions for example does not condition the neuromuscular
system in the same way as a long distance event.
Periodization
The concept of
periodization is key to sport-specific strength training. Dividing the overall training plan into succinct phases or periods,
each with a specific outcome, allows sport-specific strength to peak at the right times, whilst minimizing the risk of over-training.
It also allows more specific
elements of strength to be built on a solid and more general fitness foundation. Athletes cannot progress week-in week-out
indefinitely so periodization permits variations in intensity and volume to promote performance enhancements for as long as
possible.
Speed Training
What is speed?
It is the ability to reach a high velocity of movement in whatever mode of locomotion – running, cycling, skating swimming
etc (1).
Very often, agility
is more relevant to successful sports performance than all-out speed. Agility is the ability to explosively break, change
direction and accelerate again.
Another element
of fitness closely related to speed training is speed endurance. Many athletes must maintain a high velocity for longer than
6 seconds or produce repeated sprints with minimal rest periods in between.
The combination of speed,
agility and speed endurance an athlete requires is determined by his or her sport. But regardless of the event, there are
several modes of training that are integral to developing a ‘fast’ athlete:
Strength &
Power Training
Speed is chiefly
determined by the capacity to apply a large amount of force in a short period of time. This is also known as power. Many athletic
movements take place in 0.1 to 0.2 seconds but maximal force production takes 0.6 to 0.8 seconds. The athlete who can apply
most force in the short period of available time is said to be the most powerful.
Strength training
increases maximal force production. Assuming as a result, more force can be produced in the same period of time, strength
training alone can increase power. However, it makes more sense to increase both maximal force production and the rate of
force development. This can be achieved through power training. Both strength and power training are integral to improvement
of speed.
What can help?
Practicing moving
and accelerating faster helps to condition the neuromuscular system to improve the firing patterns of fast twitch muscle fibers.
Two variations of basic speed training are assisted and resisted speed training. Assisted training (also called over speed
training helps to improve stride frequency (2,3,4). Resisted speed training helps to improve speed-strength and stride length
(2,3,4).
Agility Training
Most team sports
consist of very few movements that occur only in a straight line. Nor do those movements occur at a fixed pace or for a fixed
length of time. Agility and quickness training improves an athlete’s ability to change direction, brake suddenly and
perform sport-specific skills with speed and dexterity.
Compare speed training to
strength training for a moment. A sport-specific strength training program will first aim to develop basic strength. This
is on the premise that a solid base of strength offers greater physical potential to work with when converting it to sport-specific
strength later on. Basic speed training along with power training maximizes the athlete’s ability to move rapidly. Agility
training helps an athlete to apply their speed to sport-specific scenarios.
Plyometrics
A muscle that is stretched before a concentric contraction, will contract
more forcefully and more rapidly (4,5). A classic example is a “dip" just prior to a vertical jump. By lowering the
center of gravity quickly, the muscles involved in the jump are momentarily stretched producing a more powerful movement.
But why does this occur? Notice the counter-movement Two models have been proposed to explain this phenomenon. The first is
the…
Mechanical Model
In this model,
elastic energy is created in the muscles and tendons and stored as a result of a rapid stretch (6,7,8). This stored energy
is then released when the stretch is followed immediately by a concentric muscle action. According to Hill (9) the effect
is like that of stretching a spring, which wants to return to its natural length. The spring is this case a component of the
muscles and tendons called the series elastic component. The second model is the…
Neurophysical
Model
When a quick
stretch is detected in the muscles, an involuntary, protective response occurs to prevent overstretching and injury. This
response is known as the stretch reflex. The stretch reflex increases the activity in the muscles undergoing the stretch or
eccentric muscle action, allowing it to act much more forcefully. The result is a powerful braking effect and the potential
for a powerful concentric muscle action (10,11,12).
If the concentric
muscle action does not occur immediately after the pre-stretch, the potential energy produced by the stretch reflex response
is lost. (i.e. if there is a delay between dipping down and then jumping up, the effect of the counter-dip is lost).
It is thought that both the
mechanical model (series elastic component) and the neurophysical model (stretch reflex) increase the rate of force production
during plyometrics exercises (6,7,8,10,11,12).
