With summer just around the corner, a seasonal array of exercise opportunities are available to shake up your exercise routine. One way to dive into summer is by diving into the water itself. Anyone can benefit from aquatic exercise, also known as water-based exercise (WBE), because it is so versatile; there are numerous ways to get a well-rounded workout.¹ In this article, we discuss the three main types of WBE, how aquatic exercise engages the body, and the unique benefits of these workouts.

TYPES OF AQUATIC EXERCISE

The three main types of WBE—swimming, shallow-water aquatic training, and deep-water aquatic training—fall under the same umbrella of aquatic exercise.² The American College of Sports Medicine defines aquatic exercise as structured physical activity that “is done in a body of water, such as a pool, lake, or the ocean.”³

Swimming. The first type of aquatic exercise is swimming. For the purposes of this article, we will focus on lap swimming and exclude recreational and leisure swimming. Lap swimming can be done consistently or with short breaks at the end of each lap.⁴ This WBE focuses on consistent, repeated movement and strength training.

Shallow-water training. The second type of aquatic exercise is shallow-water training. This WBE is typically performed in a depth of four to five feet or when the water reaches the middle of the ribcage or chest.² This provides the benefits of reduced impact and grounding forces, which allows for proper body alignment and movement control. One of the main types of shallow-water training is water aerobics. This WBE focuses on muscle toning, flexibility, and coordination.

Deep-water training. The third type of aquatic exercise is deep-water training. This WBE is performed suspended in a depth that allows the body to remain suspended in the water while not touching the bottom of the pool.² Deep-water training may include use of flotation equipment, such as a swim belt or pool noodle, to help maintain proper body alignment. Water aerobics and aqua jogging are two popular types of deep-water training. This WBE focuses on muscle toning, endurance, and coordination.

A FULL BODY STRENGTH WORKOUT

Aquatic exercise is a full body workout. From swimming laps to treading water, WBE allows the body to work smarter rather than just harder. This is largely due to resistance—experts estimate that water is 800 times as dense as air.^5,6 Additionally, WBE targets many areas of the body, from the head to the toes.

Arms. The arms are one of the primary muscle groups that allow the body to move through the water. From the fingertips to the shoulders, nearly the entire arm fights water resistance.⁷ By forming an anchor point with the arm, the body can propel itself forward by pushing or pulling water. Most people only use their hands (with their fingers together and curved inward) as an anchor point, but engaging the forearms and upper arms can create a more powerful movement. Whether swimming or pushing buoyant exercise equipment under the surface, the arms will be fully engaged.

Back. If you press your hands into your back behind your ribcage, you can feel the latissimus dorsi, more commonly known as lats. This triangular, flat muscle—the largest muscle in the upper part of the body—fights water resistance by supporting, extending, and rotating the shoulders and arms.⁸

Core. Because the water keeps the body buoyant, WBE requires a certain level of control the body’s midsection. This activates and engages the deeper muscles in the core, which consist of abdominal muscles, obliques, diaphragm, pelvic floor, trunk extensors, and hip flexors.^9,10 Any time the body is moving itself through the water, even if it’s just treading water, the core is engaged.

Quads. While the legs are a heavy part of the body, they are also the most powerful. Aquatic exercise often involves kicking the legs to move through the water, and a strong kick requires strong quads and hip muscles.⁷ These muscles are strengthened through the whipping action of the legs to stay afloat and underwater exercises, such as leg raises and curls.

Ankles and calves. Similar to the quads, WBE increases ankle and calf strength. Those muscles contract each time you push off the wall or from the bottom of the pool.⁷ Isolating these areas using pool fins or a buoyancy bar can target these small but important muscles. 

BENEFITS OF AQUATIC EXERCISE

Good form of aerobic and anaerobic exercise. Most WBE activities address two areas of conditioning: aerobic and anaerobic exercise.⁷ Put simply, aerobic exercise builds endurance by increasing heart rate and breathing for an extended period of time, while anaerobic exercise involves short bursts of intense activity.^11-13 For example, swimming laps at a consistent speed for an extended period of time is an aerobic exercise, while swimming as fast as you can for a finite amount of time (e.g., 10 seconds) is considered anaerobic. Participating in these two types of conditioning allows the body to balance burning calories and building muscle mass.^14,15 Engaging in aerobic and anaerobic exercise can also keep your workouts fresh and exciting.

Improves heart and lung function. Both aerobic and anaerobic exercises have unique and cumulative positive effects on cardiovascular health.¹⁶ The heart rate and breathing naturally increase during exercise because the body needs more oxygen.¹⁵ The heart works hard to pump oxygenated blood to other parts of the body, which strengthens muscles around this organ.^17-19 And because you are forced to modulate your breathing when your head goes under water during WBE, the lungs become more efficient at meeting the body’s demands for more oxygen, which can even result in structural changes, such as increased lung capacity, over time.¹⁵

Low impact on joints. In many cases, WBE can be a complementary part of a treatment regimen for pain.^3,7,9,20,21 People with chronic pain, such as arthritis, osteoporosis, or fibromyalgia, or those seeking to rehabilitate an injury make excellent candidates for aquatic exercise. The buoyancy of the water provides a non- or very-low-impact environment for exercise by preventing significant stress on joints or injured areas. In addition to temporarily providing pain relief, WBE provides an opportunity for people to build muscle via water resistance.^22,23 The buoyancy also helps distributes body weight more equally, allowing a broader range of motion and more loose, flexible joints and ligaments, which can prevent further damage while improving mobility, posture, and muscle coordination.²⁴

Boosts psychological well-being. If exposure to visible outdoor bodies of water can benefit a person’s mental health, imagine the effect of diving into it.²⁵ Research resoundingly supports the hypothesis that the therapeutic effects of water exposure alongside the therapeutic benefits of exercise establishes WBE as an effective mental health intervention.¹ According to a 2022 review published in Complementary Therapies in Medicine, numerous studies have shown that aquatic exercise, especially water aerobics, can ease the symptoms of certain mental disorders, such as depression, anxiety, and ADHD.^1,27-31 More generally, WBE can alleviate mental stress.^1,17,32-34 It does this in several ways, including providing a sense of community, boosting endorphins, and improving focus.

BOTTOM LINE

Whether you’re in the pool or open water, WBE is just one way to make a splash this summer. Aquatic exercise is versatile, offering various workouts in a variety of settings, levels of intensity, and programs for all ages and abilities. The three widely accepted types of WBE—swimming, shallow-water training, and deep-water training—engage nearly all areas of the body with a focus on strength, endurance, power, and flexibility. The health benefits of aquatic exercise are equally diverse, ranging from psychological to physiological, and can cater to each individual’s specific needs. If you’re looking for a way to cool off this summer, take a deep breath and hop into the water! You never know what you’ll find under the surface.

SOURCES

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