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ARMS
The arms are extremely important in swimming because they are the link between the primary force-generating muscles of the upper extremity, the latissimus dorsi and pectoralis major, and the hands and forearms, which are the anchor points that propel the swimmer through the water. Chapter 1 compared the body to a chain that starts at the hands and extends all the way down to the feet. The main point was that, as a swimmer moves through the water, movements and forces are transmitted along the chain and that the chain is only as strong as its weakest link. Of course, the arm muscles also aid in generating the forces that propel you through the water. Those reasons should help you understand the importance of targeting the arm muscles with a dryland program.
The elbow divides the arm into an upper and lower component. The elbow is a hinge joint restricted to two movements, extension and flexion. Elbow extension occurs when you straighten your arm, moving the forearm away from the upper arm. Elbow flexion is the opposite, involving bending the forearm toward the upper arm. The structural framework of the upper arm is the humerus. The lower arm, typically called the forearm (figure 2.1, a-b), is supported by the radius and ulna. These three bones are the major attachment sites and levers upon which the muscles of the arm and forearm originate and act on. The two primary muscle groups in the arms that are the target of the strengthening exercises in this chapter are the elbow extensors and elbow flexors. Both contribute to the maintenance of proper arm position and propulsion during each of the four competitive strokes.
Figure 2.1 Forearm: (a)front and (b)back.
The primary elbow extensor is the triceps brachii (figure 2.2). Tricepsrefers to its three heads of proximal attachment, and brachii refers to its origination in the arm. The medial and lateral heads arise from attachment sites on the humerus, and the long head crosses the shoulder joint and arises from the scapula (shoulder blade). The three heads unite to form the tendon that crosses behind the elbow joint and inserts onto the olecranon process of the ulna. The olecranon process forms the tip of the elbow when it is bent to 90 degrees. A much smaller triangular muscle called the anconeus assists the triceps in extending the elbow joint and is important as an elbow stabilizer. The anconeus is intimate with the lateral head of the triceps brachii; sometimes the fibers of the two muscles blend into one another.
The primary elbow flexors are the biceps brachii and the brachialis (figure 2.3). As the name implies, the biceps has two heads, a long and a short, both of which cross the shoulder joint and attach to the scapula. The two heads fuse to form a common tendon that crosses the front of the elbow joint to attach to the radius approximately 1.5 inches (4 cm) past the elbow. Besides being an elbow flexor, the biceps brachii contributes to the forearm movement of supination, which is the position when the palm is facing up. Your hands would be in this position to carry a bowl of soup. The brachialis lies beneath the biceps brachii and arises at the midpoint of the humerus. It attaches to the ulna just after it passes anteriorly to (in front of) the elbow joint. A smaller muscle that at times contributes to elbow flexion is the brachioradialis. This muscle arises from the lateral aspect of the humerus just above the elbow and travels along the outer part of the forearm to attach to the radius just above the wrist joint.
Despite difference in stroke mechanics, freestyle, butterfly, and backstroke have similar activation patterns of the elbow flexors and extensors during the pull phase. As the swimmer progresses through the catch, the elbow moves from full extension to a position of 30 to 90 degrees of elbow flexion at midpull, depending on the stroke and the swimmer’s mechanics. The primary muscles responsible for generating the change in elbow position and, when necessary, maintaining the elbow in a fixed position of flexion are the biceps brachii and brachialis. After the elbow reaches a point of maximal flexion during the midpull, it progresses into an extended position during the remainder of the pull phase. This action aids in generating propulsive forces and is brought about primarily by active recruitment of the triceps brachii. The degree of the propulsive force generated depends on the point in the pull phase at which the swimmer removes the hand from the water to initiate the recovery phase. In freestyle and butterfly many coaches are now teaching their swimmers to begin the recovery process as the hand reaches the hip, before the elbow is fully extended. Meanwhile, backstroke mechanics involve the catch phase, terminating with full extension of the elbow joint.
Figure 2.2 Triceps brachii.
Figure 2.3 Biceps brachii, brachialis, and brachioradialis.
Unlike in the other strokes, during the initial portion of the pull phase of the breaststroke the triceps brachii is the primary muscle that is active at the elbow joint, functioning to maintain the elbow in a position near full extension. As the hands begin to turn inward marking the transition from the outsweep to the insweep, the muscle activation patterns at the elbow begin to change. The elbow flexors (biceps brachii and brachialis) activate to bring the elbow into a flexed position, a movement that aids in the generation of propulsive force. As the swimmer transitions into the recovery phase, the recruitment pattern changes again. The triceps brachii becomes activated to extend the elbow joint, thereby straightening the arm and preparing the swimmer to begin the next pull phase.
As you read through the remainder of the chapter you will see that several of the exercises involve movement at a single joint, the elbow, specifically targeting only the elbow extensors (triceps brachii) or the elbow flexors (biceps brachii and brachialis). These isolation exercises are best placed at the end of your dryland program to avoid fatiguing a single muscle group early in the workout program. A final consideration is that between the two muscle groups, the elbow extensors are more active during the swimming movements. Therefore, you should aim for a 2:1 ratio between exercises that target the extensors and the flexors.
When performing upper-body exercises, be sure to set the shoulder blades for stability before performing the exercise. For any exercise, set the core as well. See the sidebar below for instructions about how to do this.
Setting the Shoulder Blades and the Core
Setting the shoulder blades:When performing upper-extremity exercises, particularly those that target the shoulder joint, you should set the shoulder blades into a stable position. The setting movement involves pinching the shoulder blades backward and downward, as if you were trying to put your shoulder blades in the back pockets of your pants. In the process of setting the shoulder blades, avoid shrugging the shoulders upward because this action shifts the focus of the exercise from the lower fibers of the trapezius muscle to the upper fibers, which are typically already overdeveloped in most swimmers.
Setting the core:Before performing any exercise you should make a conscious effort to set the core. By setting the core you establish a foundation of support upon which the exercising muscles are able to exert their forces. You should also stabilize the low back, reducing the risk of injury. Setting the core involves simultaneously contracting the abdominal, low back, and gluteal muscles as if they are a corset that encircles the abdominal region. See chapter 5, page 87, for more information about setting the core.
Standing Double-Arm Triceps Pushdown
Execution
1. Stand facing a pulley machine with a high cable attachment. Grasp the handlebar at chest level using an overhand grip so that your hands are slightly less than shoulder-width apart.
2. Holding your elbows tight at your sides, extend the forearms until the elbows are almost locked.
3. Slowly lower the weight stack until it is 1 inch (2.5 cm) above the resting stack and your hands are back to the start position.
Muscles Involved
Primary:Triceps brachii
Secondary:Anconeus, wrist and finger flexors
Swimming Focus
Although this exercise is effective at targeting the triceps brachii and will produce benefits across all four strokes, it is particularly valuable to breaststrokers because it mimics the final portion of the underwater pull performed off the start and each turn wall.
When performing the exercise you should maintain an upright posture and try to generate the force necessary to move the weight solely by tightening your triceps brachii. Because swimmers have a predisposition to a rounded-shoulder posture, you can easily develop the bad habit of leaning into the cable and cheating by bouncing your upper body at the start of each repetition.
VARIATION
Standing Double-Arm Triceps Pushdown With Rope
In the starting position your hands are at your midline. As the elbows are extended, the hands pull the ends of the ropes outward so that when the elbows are almost locked the hands are shoulder-width apart. The added lateral movement isolates the lateral head of the triceps brachii.
Dumbbell Kickback
Execution
1. Holding a dumbbell in one hand, support your upper body with your free hand and a knee on an exercise bench.
2. With your upper arm parallel to the floor and your forearm vertical, raise the dumbbell upward until the elbow is almost locked.
3. Lower the dumbbell back to the 90-degree bent-elbow position.
Muscles Involved
Primary:Triceps brachii
Secondary:Posterior deltoid, latissimus dorsi, anconeus, wrist and finger flexors
Swimming Focus
Dumbbell kickbacks help strengthen the triceps brachii because they move the elbow through the final 90 degrees of extension, an important range when trying to enhance the propulsive forces generated during the final portion of the pull during freestyle, butterfly, and especially backstroke.
Slow, controlled movements are the key to maximizing the benefits of this exercise. The best way to enforce this is to pause for one to two seconds when the arm is fully extended, with a focus on squeezing the triceps tight, and to pause for one to two seconds when the arm is in the 90-degree bent-elbow position. This approach will prevent you from generating a pendulum-like swinging motion with the dumbbell, which is a form of cheating.