As most experienced aquatic fitness professionals know, moving a limb through water – as compared to air – increases exercise resistance by approximately 12%. This is why your workout in the pool can be more strenuous and strength-oriented than a traditional land workout (without weights or added resistance equipment). One can exercise at a slower more controlled pace in the water and still experience the benefits of traditional land exercise regimes. Hence, it seems common knowledge for aquatic professionals to naturally assume that it is "always" more strenuous for the limbs (specifically, the arms) to perform a movement in the water than out of the water. When analysing whether or not to take the arms out of the water, we must look at several factors that affect exercise intensity and exercise purpose. Aquatic exercise intensity is affected by various aquatics theories, one being eddy drag.
The theory of eddy drag addresses the whirlpool effect that is created by the limbs as they move through the water. When reversing the direction of movements quickly, the body has to work that much harder to move against the current. Movements forward require an equal, if not harder, effort to move backward. For example, a straight leg kick front engages the hip-flexor and the quadriceps, the reverse leg kick (or extension) back engages the gluteal and the hamstring in a more challenging effort. Therefore, when working in the pool it is difficult to reverse directions too quickly. You must give yourself ample time to reverse directions. Also, you must realise that while whirlpools create resistance, they also create assistance. Arm movements in the pool do not necessarily create more resistance.
Each movement by each separate limb creates its own whirlpool. These whirlpools can either complement or contradict each other. Consider an arm movement that is synchronised with a leg movement. A simple example of this is a freestyle swimming type arm movement that assists an exerciser to move forward through the water while they water walk. The whirlpool created by the arms actually assists with the movement of the legs.
However, consider if the arm movements were in opposition to the legs. The whirlpools created by the legs would be in contradiction (or opposition) to the whirlpools created by the arms. This would create a more strenuous or challenging workout. Therefore, aquatic arm movements can either assist or resist leg movements.
There does, however, remain one more option for arm involvement; arms can remain neutral. Neutral arm movements neither assist nor resist leg movements. While trying to move forward in the water, aquatic arms may assist you by "swimming" forward or resist you by "pushing backward". A neutral arm may remain out of the water.
When water is chest deep, a neutral arm would be above water level, or shoulder level or above. Holding the arms out of the pool would be harder than using the arms in a "swimming" motion forward to assist the legs. Further, taking the arms out of the water during water walking would be more difficult in terms of balance and control. There would be no arms available to stabilise your forward movement. You would expend more energy to remain stable, engaging the core muscles, the abdominals, erector spinae, Latissimus dorsi and leg muscles, to maintain body alignment and forward movement against the resistance of the water.
Therefore, the commonly held belief that arms in the water always creates a more strenuous workout is simply not true.
There is another misconception that because arm movements out of the water can move faster than legs in the water, having the arm out of the water is unsafe. This is also not true. It is important to know, however, that there will be a dramatic difference between moving body parts out of the water and moving body parts in the water. It is also important to note that this difference takes time to get used to.
Yet, the imbalance of resistance between upper body limbs and lower body limbs actually forces the body to develop its kinesthetic awareness and challenge the core (torso) musculature during stabilisation. Simply put, the muscles of the core will contract to stabilise and synchronise the movements of the upper and lower body. This may create a tougher and more strenuous workout.
Another misconception dealing with arm movements out of the water is that because of the theories of lever length and surface space, re-immersing the arms into the water after taking the arms out of the water is necessarily unsafe.
The laws of leverage analyse how the size and length of the object being moved through the water influences the energy required to complete that move. Compare moving a ping pong paddle as opposed to a hockey stick through the water. Moving a hockey stick would be much harder since it is further away from the body. Greater leverage and thus, greater effort is required to move the object. Surface space refers to both the size (and angle) of the object being moved through the water. For example, extending the arm away from the body and moving an open palm through the water is harder when the palm is cupped and pushes the water side to side rather than if the hand is palm-down and slices through the water.
If we keep the theory of lever length and surface space in mind when we re-immerse the arms into the water, we can maintain a safe workout. To re-immerse the arms back into the water after taking the arms out of the water, you must reduce the lever length and reduce the surface space of the arm and hand. This means that the hands must be brought in close to the body, instead of being held away from the body or out to the side or front. Further, the hands must slice into the water with the fingertips first and not slap into the water with an open palm. The position may look like a "chicken arm" or "cleavage" position. This is one such position that will serve to reduce both lever length and surface space and make for a safe re-immersion into the water.
The other safety concern regarding taking arms out of the water is extending the arms above the head. There is a misconception that taking the arms over the head puts undue stress on the back and places the back into hyperextension. Firstly, “arms over the head” does not mean arms extending behind the head. “Arms above the head” refers to arms extending up and reaching slightly forward as if extending out from the eyebrows. This reduces the temptation to arch the back when the arms are above the head. Yet, even if the arms are directly above the head, the back is not in hyperextension, it is merely in extension.
It must also be remembered that because of the buoyancy of the water and the reduction of gravitational pull on the spine, the risk of injury to the back is greatly reduced in the pool. The disks and vertebrae are under much less stress and pressure because of this buoyant environment.
Further, arms above the head is a natural position. People reach up all the time, whether it is to grab a box of cereal or wave goodbye to friend. We need to encourage full range of motion for all our clients.
It is in no way recommended that the arms remain out of the water for an extended period of time. This would put extreme stress on the shoulder girdle and on the deltoids. Additionally, arms are usually taken out of the water to accentuate creativity, but extended or repeated arm movements in one position may actually serve to limit creativity. A 25% or less arm movements out of the water to a 75% or more arm movements in the water ratio is much more logical.
Also, there may be a misbelief that arms out of the water are actually more strenuous because they elevate the heart rate. However, according the "pressor response", while it is true that arms elevated above the heart increase the heart rate, they do not increase energy expenditure.
According to the "pressor response" which is supported by numerous studies, arms lifted above the head make the heart work harder to pump the blood up against gravity. The exerciser does not burn more calories or increase the cardiovascular response because of this position. Thus, while the heart rate may go up because the arms are elevated, prolonged elevation does not increase fat burning or improve cardiovascular fitness. Arm movements out of the water must vary their position and be controlled in their patterns and speed. As in all exercise programmes, common sense must be used.
While we have analysed the effectiveness of taking the arms out of the water and the safety aspects of taking the arms out of the water, we have yet to analyse the creativity aspect. How and why do our students keep returning to our class week after week and year after year? The answer is simple creativity!
It is fun to see an entire class doing a creative arm pattern all together. It provides variety, challenge and a sense of adventure. Don’t look at arms out of the water as a risk; look at arms out of the water as a reward!