Lets face it Partial range repetitions can be far more effective than
full-range reps for building strength and muscle in as short a time as
possible. They are basically reps done in a specific range of motion and
usually involve doing only the top half or top six inches of the movement
this is in your strongest range of motion.
By working only in this range of motion you can use far more weight and
therefore, work your muscles harder because they can handle more resistance.
Partial range rep exercises have advantages of being safer also because the
weight is prevented from entering the weakest range of motion where most
injuries occur.
These can be applied to almost any exercise but are more appropriate for
some exercises than others. These include the bigger compound exercises such
as the Bench press, Leg press and Reverse grip lat pulldown.
Lets take the bench press for example, after performing a Full range rep
warm-up, move to a smith machine or power rack (or a good spotting partner)
and place the supports so the bar rests at the top half range (or six
inches) from your reach so when you lie on the bench and reach up to grab
the bar your arms should be about six inches from full extension.
Push the bar to the top of the movement and then back to the supports.
Notice how the safety bars prevent the weight from entering the weak range
of motion. Continue on to total failure.
When you lift weight in your strongest range of motion you will notice how
easy it is! You will be able to use twice the amount of weight that you
would use with the Full Range Reps.
Isometric Contraction is another step upwards in the intensity stakes. It is
performed by holding a weight in a fixed position with the muscle fully
contracted for an extended period of time. It is performed using the one set
only for holds of between five and fifteen seconds.
During these holds nearly all of the muscle fibers of the target muscle are
recruited, something that doesn't happen with full range repetitions. The
more muscle fibers you can recruit the more growth that can occur. I have
found that by using this technique on trainees strength gains of 50% in ten
weeks have often occurred.
Only one all out maximum intensity set per exercise is necessary for this
type of training. If you give the first set 100% effort then there will be
no more requirement for further muscle stimulation on that specific
exercise.
Fortunately isometric contraction will probably be the easiest and safest
way to perform strength training exercises as there are no reps and no
motion of the weight, the entire set consists of holding the weight
motionless for 5-15 seconds depending on what cycle you are in.
By cycling the seconds per hold, as you move into your training program from
week to week the absolute intensity of the exercise increases (the weight
used for the exercises increases) thus promoting more functional muscle
growth. It is very important you limit the range of motion of the weight you
are using.
If you do not have a strong training partner who can spot you during these
lifts then you must use a power rack or a smith machine. Now lets look at a
exercise and how isometric contraction works with it.
Bench Press: This exercise is best performed on a smith machine or inside a
Power Rack, Position the bar within two or three inches of your extended
reach. Place 50-100% more weight on the bar than you have been using for
your partial reps. Push the bar up two to three inches (do not lock-out) and
hold for appropriate count.
With all exercises push yourself to the limits of your capability. Most
trainee's using this method make the mistake of underestimating the weight
they can lift. You can expect very significant increases in the weight used
for all exercises.
So there you have it, by incorporating these two training techniques into
your every day strength training programs you will be well on the way to
increasing your size and strength in no time at all.
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Catapult Your Muscle Gains With Partial Reps and Isometric Contraction 
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