By Stefan Ianev
So far in this ‘train like a pro’ series we have looked at exercise selection, volume, and intensity as part of the 7 acute training variables that we can manipulate to achieve a desired training effect. Understanding these variables and when to apply them is extremely important for any personal trainer or trainee looking to optimize their program design.
Here is a recap at what we have covered so far:
- Beginners should generally perform 1-2 exercises per body part for 3-4 sets of 10-15 reps each
- Intermediates should generally perform 2-3 exercise per body part for 3-4 sets of 6-12 reps each
- Advanced clients should generally perform 3-4 exercises per body part for 4-5 sets of 6-12 reps each and occasionally using fewer or more repetitions
This week we are going to look at type of contraction. This is one of the variables that often is not given much attention by the general public but bodybuilders and athletes over the years have used various types of contractions to stimulate maximal strength and hypertrophy.
There are 3 basic types of muscle contractions:
- Concentric – This is when the muscle shortens under load
- Isometric – This is when the muscle remains static under load
- Eccentric – This is when the muscle lengthens under load
During a regular dynamic contraction where you lift a weigh up and down under control until momentary muscle failure is reached only the concentric portion of the lift is fully exhausted.
Furthermore only the portion of the lift where mechanical advantage is lowest is where failure will occur. For mid-range movements this will generally be the mid position, for stretch position movements this will generally be near the bottom position, and for peak contraction movements it will generally be near the top.
For beginners and intermediates just working to concentric failure on a variety of movements to stimulate different points in the strength curve will provide a sufficient stimulus, but the progress will come to a linear stall eventually and the need for a new stimulus is needed to keep moving forward.
Occasionally if someone has a weak mind muscle connection for a given muscle I might employ isometric pauses at the bottom position and/or peak contraction. I will also slow down the tempo and have them focus on flexing the target muscle as hard as possible during the entire lift. A technique which Milos Sarcev refers to as Isotension and Ben Pakulski refers to as Intentions.
When you apply this technique you will use far less load on the bar because you are generating an internal torque when you flex the muscle through the movement. This is also effective for creating more even tension throughout a movement as you will be able to apply greater internal torque at those points where external torque is lower. In other words you will create a greater mean torque.
Something that I apply to my intermediate and advanced clients at our Sydney CBD and Chatswood gyms who have already developed a good mind muscle connection it would also be beneficial to employ explosive reps to maximize peak torque (1). This is because force equals mass x acceleration, so moving the bar faster increases peak torque.
However, most of the torque will occur near the bottom of the movement, since due to momentum you lose tension near the top (2). For this reason it is best to also perform some controlled reps as well. In fact Arnold who was well known for having the world’s greatest biceps was a big fan of doing cheat barbell curls which he attributes to his incredible biceps mass.
Cheat reps due to their explosive nature can amplify torque near the bottom of a movement by 2 to 3 fold. However they can also be very taxing on the joints and should be used sparingly. Arnold only did about 20% of his curls in cheating style. The rest of the time he was much stricter and often used peak contraction.
For very advanced athletes it can be beneficial to employ shock techniques where isometric and eccentric failure is reached. This can be done immediately after a set where concentric failure is reached or as standalone sets. Functional isometrics which were popularized by world renowned strength coach Charles Poliquin have been used by many athletes to break through strength plateaus.
Isometric holds can also be performed after a regular set to failure at various points along the strength curve depending on the exercise. This has the benefit of increasing strength in a particular range within a movement and also increasing metabolic stress due to local build-up of metabolites within the muscle.
Eccentric only reps can be performed with supra-maximal loads after reaching failure or as standalone sets. Since eccentric contractions are associated with greater muscle damage and tissue remodeling they are a very effective training stimulus for advanced trainees who are more resistant to exercise induced muscle damage (3).
However due the delayed recovery they should only be used once a week maximum and for short periods at a time. By now your starting to gather an idea of some variables to apply into your programming. In our CHFI Performance PT Level 2 we cover each of these methods in depth. Specifically how to use them and when within the training cycle you would program them in.
I hope you enjoyed this installment and hope you tune in next time as we cover one of the most controversial topics of tempo!
- Arandjelović, O. Does cheating pay: the role of externally supplied momentum on muscular force in resistance exercise. European Journal Of Applied Physiology. 2013;113(1), 135-145.
- Johnston BD, Moving Too Rapidly in Strength Training Will Unload Muscles and Limit Full Range Strength Development Adaptation. Journal of Exercise Physiology. 2005 Jun; Vol 8 No 3
- Roig M, O’Brien K, Kirk G, Murray R, McKinnon P, Shadgan B, Reid WD. The effects of eccentric versus concentric resistance training on muscle strength and mass in healthy adults: a systematic review with meta-analysis. Br J Sports Med. 2009 Aug;43(8):556-68.