UB-TRICEPS-X

Triceps Review – Beardsley

#1. Internal moment arm lengths – elbow angle

– The three heads of the triceps brachii, Long, Lateral, Medial, have different origins but similar insertions.
– The lateral and medial heads can be subdivided into proximal and distal regions, which have different leverages depending on the elbow joint angle.
– Exercises that involve peak forces in full elbow extension (like close grip bench presses against bands or chains) will preferentially develop the proximal region of the lateral head and the distal region of the medial head
– Exercises that involve peak forces in elbow flexion will preferentially develop the distal region of the lateral head and the proximal region of the medial head.

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#2. Internal moment arm lengths – shoulder angle

– Exercises that involve different shoulder positions will produce greater hypertrophy in different parts of the triceps brachii
– When the arms are close to the sides of the body (such as in standing triceps cable pushdowns), the long head will be preferentially activated
– When the arms are overhead (such as in overhead presses, overhead triceps extensions), the medial and lateral heads will be preferentially activated.
– These results are supported by studies that have measured the muscle activation of the long head and lateral head of the triceps brachii during isometric contractions with different shoulder positions.
– The long head is more active when the arms are by the sides of the body (and also with the wrist in supination, curiously), while the lateral head is more active when the arms are at shoulder height (and with the wrist in neutral).

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#3. Inter-segmental coordination

– Research into the behavior of two-joint muscles like the hamstrings and the rectus femoris has shown that their activation is reduced during multi-joint exercises
(Ex: when performing hip extension at the same time as knee extension, hamstrings activation and rectus femoris activation are both reduced. This is probably because the hamstrings produce both hip extension and knee flexion forces, while the rectus femoris produces both hip flexion and knee extension forces. Thus, hamstrings activation would be inefficient as it would reduce knee extension force, and rectus femoris activation would be inefficient because it would reduce hip extension force. So the activation of these muscles is reduced and the activation of the single-joint quadriceps and probably also the adductor magnus is increased).
– Since the triceps brachii long head is an effective shoulder extensor, especially at 90º of shoulder elevation where the bench press is performed, its activation will probably also be suppressed during this movement.
– Therefore, it seems likely that the triceps brachii long head is less active during multi-joint pressing movements compared to the medial and lateral heads.
– Recent long-term strength training studies have largely confirmed this phenomenon since they have reported that the lateral head is preferentially developed by multi-joint pressing exercises, while single-joint triceps extensions are better for the long head.

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#4. Sarcomere lengths

– Historically, it has often been assumed that strength training with a long maximum muscle length at the end of each rep (often in conjunction with a larger range of motion) will always produce greater hypertrophy. However, the triceps brachii consistently fails to display this tendency.
– Researchers have often attempted to “explain away” these results by suggesting that the particular exercises or study designs were not appropriate for determining the effects of strength training with long or short maximum muscle lengths. Nevertheless, there is an alternative physiological explanation.
– The amount of passive tension that a muscle fiber can produce during a stretch depends on the length that titin reaches during the stretch. Titin length during a stretch is determined by the number of sarcomeres in series in the muscle fiber. When a muscle fiber has a lot of sarcomeres in series, each sarcomere (and therefore each titin molecule) does not stretch very far. Conversely, when a muscle fiber has few sarcomeres in series, each sarcomere (and therefore each titin molecule) stretches a long way. Titin typically only starts to produce passive force during a passive muscle stretch when the sarcomere reaches a point called the “descending limb” of the length-tension relationship. Researchers have shown that the sarcomeres of the triceps brachii tend not to reach this point during a normal strength training exercise.

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#5. Recovery capacity

– The triceps brachii recovers much more slowly than most of the other muscles in the body, although it is not typically a muscle that often experiences a great deal of delayed onset muscle soreness (DOMS).
– This is a good example of why using DOMS to infer recovery status is not particularly helpful.
– Nevertheless, this suggests that for the triceps brachii, the optimal training frequency for a given amount of workout volume will be lower than for workouts that target other muscle groups.
– The triceps brachii likely recovers slower than most other muscles partly due to the extremely high proportion of fast twitch muscle fibers that it contains. Fast twitch muscle fibers are more easily damaged after exercise because they have fewer mitochondria. Thus, they experience greater damage from the calpains (proteases) that are released in response to the influx of calcium ions during exercise.
– Additionally, the very high voluntary activation capacity of the muscle means that more of the fast twitch fibers that are present inside the muscle can actually be activated during maximal efforts.

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EMG STUDIES

TRICEPS LONG HEAD & LATERAL HEAD
– Narrow Grip Bench, L-Dips, Kickbacks, Rope & Bar Pushdown, Overhead & Supine Extension

ACE Study Identifies Best Triceps Exercises – 2010 – PDF File .
– University of Wisconsin/La Crosse Exercise and Health Program; John Porcari, Ph.D., and Brittany Boehler, B.S.
Procedure
– 15 female subjects, ages 20 to 24; All subjects had previous weight-training experience to ensure proper exercise technique
Results
Triceps Long Head: Kickbacks 90 . L-Dips 90 . Overhead Ext 80 . Rope Pushdown 80 . Bar Pushdown 75 . Supine Ext 70 . Close Grip Bench 60
Triceps Lateral Head: Kickbacks 90 . L-Dips 90 . Overhead Ext 70 . Rope Pushdown 70 . Bar Pushdown 60 . Close Grip Bench 65 . Supine Ext 55