Weight Loss through Aquatic Exercise

Abstract

Obesity is one of the main causes of unwanted health-related issues. Obese people have a more limited ability to keep fit although they are seriously willing to do exercise and improve their physical fitness. While there are numerous methods and programs to reduce weight through land-based exercises, there still exist reluctance, discomfort and risks of injury during exercise for obese people. However, an effective exercise program should plan at a moderate intensity level with low-perceived exertion for obese people. Then aquatic exercise can be purposed as a convenience exercise without joint strain and high impact. Considering the physical properties of water, aquatic aerobic exercise not only can increase metabolic demand and burn calories but immersing the body in water provides a non-weight bearing exercise option. Consequently, the relevant knowledge about aquatic exercise assists to provide proper exercise programming as well as consideration of physical fitness programs for obese who are unwilling to do land-based exercise. As a background of obesity prevalence is presented in this chapter, there are focuses on aquatic exercise definition and its benefits as well the exercise prescription for weight loss. Then, a perspective of aquatic exercise for obese people and concise guidelines are reviewed in this chapter.

1. Introduction

This chapter will explain weight loss through aquatic exercise. This section focuses on a concise of obesity prevalence, aquatic exercise definition, and its benefits for obese people. Besides that, this chapter will explain the aquatic exercise prescription designed for weight loss, as well. Hence, this chapter creates an opportunity to extend the superiority of aquatic aerobic exercise as a convenient and effective exercise training method to lose weight and improve physical fitness components, which led to the reduction of the health risk factors for different overweight and obese groups.

1.1 Obesity definition and BMI

Obesity is commonly defined as having great body mass. Then, Body Mass Index (BMI) is a term that is mostly applied to determine the weight in link to stature or height. Basically, BMI is particularly computed as an individual’s weight in kilograms divided by the square of height in meters which shows via kg·m⁻² unit. Commonly, the American College of Sports Medicine (ACSM) guidelines define the overweight class as a BMI of ≥25, the obese class as a BMI of ≥30 kg.m⁻², and the extremely obese class as a BMI of ≥40 kg.m⁻² [1], while Suissa et al., based on WHO report in 2020, have displayed the different BMI values for adult men and women across the globe [2]. In this regard, there are different BMI values for different countries worldwide, for example in South East Asia BMI of ≥28 kg.m⁻² is defined as obesity class. In addition, another accurate definition by WHO [3] considers abdominal obesity through a waist-to-hip ratio (WHR) which in men is more than 0.90 and for women, it’s a ratio of 0.81 or more.

1.2 Obesity prevalence

In general, overweight and obesity are caused by additional accumulated fat in adipose tissues which is the main cause of unwanted health-related issues. It is approximately half a century (since 1975) that obesity has almost tripled globally. Alam, and Agrawal [4] stated according to WHO report [5], more than 1.9 billion adults in the age of 18 years and older, were categorized as overweight class, while 650 million of those were in the obese class (BMI ≥30 kg.m⁻²) [4]. In addition, right before the COVID-19 pandemic (in 2019), it was estimated that 38.2 million children (<5 years old) were in the classes of overweight or obese. Even though previously overweight and obese were tabled as a problem in the high-income country, currently being overweight and obese are on the rise in low- and middle-income countries, specifically in urban settings [6]. However, the evidence displayed since 2000, the number of overweight children (<5 years old) has augmented by nearly 24% in Africa. Approximately half of these overweight or obese children (<5 years old) were in 2019 and lived in Asian countries. In 2020, also, there were 39 million children (<5 years old) were classified as overweight or obese. Meanwhile, Afshin et al., in the study entitled “Health effects of overweight and obesity in 195 countries over 25 year” stated the World Health Organization estimated that till 2018, 39% of adults were overweight and 13% of them were obese in the world. They also stated in 2015, there were overall 107.7 million obese children and 603.7 million obese adults, which is expected to rise in the future [7].

Nowadays, it is well-documented that obesity is a complicated health problem and it is outcomes from contributing several factors, such as genetics, individual behaviors (e.g., physical activity and dietary habits), the cultural and community environment. It also can be the result of the effect of disease or medications. In other words, physical inactivity, daily anxiety stressors, increasing sitting time and unhealthy food intake result in overweight and obesity. However, the rate of sitting time and sedentary lifestyle most likely will lead to obesity which indirectly can affect dramatically on cardiorespiratory health [8].

However, excess fat impairs the organs and body systems function, leading to multiple health problems and even decease. Heart disease, diabetes, hypertension, hypertriglyceridemia and some forms of cancers are altogether related to obesity and can be fatal. Meanwhile, other health disparities conditions such as low-back pain, osteoarthritis, sleep disorder, psychological impairments, and reproductive issues are also common although not life-threatening. Then, overweight and obese people need to access superior knowledge to manage their weight to an ideal and healthy condition. However, obese people need to do lifestyle modification and significantly target three key components including a healthy diet, regular exercise, as well as behavior therapy [1].

Hence, to avoid the epidemic of high cardiovascular risk conditions and the relevant diseases, such as obesity, diabetes, and hypertension people must change their sedentary lifestyles toward a physically active lifestyle. In that, engaging in physical activities such as aerobic exercise programs have been a popular choice among the obese community. Then, obese people are required to improve their health and fitness and nowadays in modern life which is more vital and valuable during their young ages.

However, metabolic demands can greatly rise during and after exercise. It is obvious these increases result in superior caloric expenditure which is highly dependent primarily on the type of exercise. On this point, particularly aquatic aerobic exercise as a convenience, non-weight bearing exercise for individuals who are obese or overweight can be recommended as a significant intervention program not only for weight loss but for the betterment of cardiovascular fitness also.

2. Aquatic exercise program for obese people

Although several research studies were directed to reduce weight and enhance well-being through exercise programs carried out on land, there still exist difficulty, discomfort and risks of injury when performing programmed exercise for obese people. Besides, the obese population has also shown reluctance to exercise due to being ashamed of their body feature.

It should be considered that the exercise programs are challenging due to the limited ability of obese people to perform the exercise more effectively without joint strain, high impact, injury risk, and the overall discomfort associated with land exercise [9]. Then, water-based exercises are also highly beneficial to overweight or obese individuals.

Meanwhile, previous studies suggested that an exercise program with moderate intensity levels and low perceived exertion should be proposed for the obese as an effective exercise program, particularly for obese people with poor mood status and low self-efficacy. Therefore, water-based exercises are a suitable alternative form of exercise for the overweight and obese population. The following sections focus on aquatic exercises and their benefits for obese people.

2.1 What is aquatic exercise?

The aquatic exercise consists of an exercise program that is performed in water. According to Aquatic Exercise Association, water-based exercise or aquatic exercise programs were first developed by the National Arthritis Foundation YMCA [10], for therapeutic medium and health care services [11]. In the past four decades, a variety of specific aquatic exercises have developed to achieve rehabilitation and fitness purposes for people with difficulty in physical exercise on land. In addition, several studies verified aquatic exercise not only can enhance the health-related fitness components including cardiovascular fitness, muscle strength and muscle endurance, flexibility and balance, but it can decrease quickly the body fat percentage of obese patients with arthritis and also among disabled population and elder people. It has also a significant multiple health outcomes and positive physical and psychological effects [11]. Moreover, an aquatic exercise program which is also entitled water aerobics, aqua aerobics, shallow or deep-water walking/jogging/running or aqua biking/spinning exercise, or similar heading names. It is reported that they are safer than land-based exercise to decrease the risk of injuries and difficulty of exercising [12].

All types of the aquatic exercises require water-immersed and typically are performed as aerobic exercises in shallow water media like a swimming pool. The aquatic exercise is mostly performed vertically, without swimming strokes skills and typically in waist-deep, chest-deep or deeper water a type of resistance training.

However, any apparent restrictions like obesity, low levels of physical fitness, locomotion difficulties caused by aging, and some disabilities, or diseases can limit the ability of people to exercise [13]. In that, due to this limitation, aquatic exercises can be offered as a suitable alternative compared to land-based exercises.

2.2 Relevant terms for aquatic exercise

Aquatic exercise as an alternative exercise program is also called:

Water exercise programs, Water-based exercise, Aqua/water aerobics, Shallow or Deep water walking/running exercise, Aqua aerobic exercise, Water-based exercise, Aqua fitness, Aqua Yoga, Aqua Zumba, Aqua cycling, Aqua spinning and so on [1].

3. Benefits of aquatic exercise for obese people

There are several advantages of aquatic exercise for the obese population including the following:

• High energy demanding (easy to burn calories)

• Improved cardiovascular stamina

• Increases vital energy

• Low impact exercise; weightless (Perceived rate of exertion is less)

• Lessens of the gravity effect

• Lessens heart disease risk factors

• Hydrostatic pressure to assist venous return

• Easier to adhere to do exercise (due to cool media, comfortable, relaxing and hidden the fatness and body shape)

• Great place to start water walking (Xiphoid depth)

• Self-selected speed

• Emphasize safety

• Provide relaxation; feel weightless

• Less fear of falling or injuring self in the water

• Mental aspects of water; reduces anxiety, depression, …

3.1 Aquatic exercise and energy expenditure

Physical properties of water allow it to be a valuable tool in physical conditioning and exercise. The density of water is determined nearly 800 times of air. Then, workout in the water media provides high level of demanding and expending energy with less essential effort to the body to burn calories in order to losing weight [9]. Furthermore, numerous studies have examined the impact of different aqua aerobic exercises on obesity and cardiovascular risk factors. They revealed the significant heightening in health advantage in elderly people similar to aerobic exercise on land [14, 15]. A previous study conducting a program of aquatic exercise (12 weeks, 3 days weekly, 70 minutes) showed significant enhancement in cardiorespiratory fitness. The study also revealed a decrease in body fat percentage (8% reduction in skin-fold thickness), an increase in peak VO₂ (12%), muscular strength, and a diminish in total cholesterol in older-adult women [16].

Furthermore, several types of research clearly indicated that obese people are effectively able to expend energy or burn calories in a vertical position of aquatic workouts. It seems that the resistance of the water makes up for the reduced workload associated while there is non-weight bearing in the buoyant media [1]. The most effective variables that increase the burning calories as energy expenditure during aquatic exercise in vertical immersion in the water include the following:

• Depth of water that effect on weight bearing, movement control, and the resistance quantity.

• Movement speed that acts on the quantity of dragging propulsion and resistance.

• Amount of force which act against the water resistance (e.g., workout intensity; more calories you burn if the work is harder).

• Length of the individual limbs, which affects the amount of resistance which encountered during moving against the water.

• Environmental aspects such as water temperature of water and air, humidity and chemicals.

Table 1 Shows the comparison of energy expenditure of the exercising in the land-based versus the water-based exercise. The energy expenditure estimated for 30 minutes workout for a person with 70 kg with xiphoid level of immersion (tolerate of 25% of total weight).

Land-based (calories)	Water- based (calories)
Walking: 102	Walking: 220
Jogging: 230	Jogging: 340
Aerobic: 175	Aerobic: 240

Table 1.

Comparing energy expenditure of aerobic activities on land vs. water (estimation for a person with 70 kg and 30 minutes workout).

3.2 Depth of immersion on weight bearing

There are numerous studies that investigated the influence of body immersion levels and the intensity of aquatic exercises. Firstly, the rate of perceived exertion (RPE; 0–10 scale; exercise intensity) is higher at the hip level immersion compared to immersion up to the chest. The increased scale of RPE may be due to the higher intensity of drag forces acting in the lower limbs, as compared to those acting in the trunk and upper limbs when partially immersed. Secondly, shallow water reduces the buoyancy and increases ground reaction force and then the changes in the neuromuscular pattern of active muscles at different levels of the body in the water.

When comparing shallow-water versus deep-water exercises, the physiological demand seems to be lower for deep-water exercises which are helpful for individuals. In total immersion position, weight-bearing is affected by the water depth owing to buoyancy as well. As Figure 1. shows, in general, weight-bearing is depending on water immersion level which determined at the seventh cervical vertebral level (C7), the xyphoid, and the anterior superior iliac (ASIS) approximately 10, 25, and 50% of their body weight, respectively [12].

Figure 1.

Depth of water immersion and weight bearing.

Then, decreasing depth of water is one way to progress lower extremity weight bearing. However, the depth of immersion can reflect static weight bearing, and effect on the speed of movement like fast or slow walking or running in water. In that, exercising in water makes feel about 90% lighter while viscosity of water creates a resistance exercise atmosphere. In another words, this condition makes water exercise, with low impact, an ideal activity for obese people. In summary, aquatic aerobic exercise will increase energy expenditure while the body immersing in water and weigh up to 90% (neck-line) less than on land and it is non-weight bearing nature [12]. Meanwhile, although a few aquatic studies reported there was no improvement in weight loss, those planned appropriate aquatic exercise programs (e.g., frequency, duration, intensity and study length) have clearly resulted in weight loss [1].

4. Precautions and contraindications

In spite of aquatic exercise program can effortlessly assist to lose weight, and improve quality of life among obese population, many obese still have limitation and difficulty to join the aquatic exercise. Therefore, while the advantages of aquatic exercise are considerable, the potential risks also should be determined to create appropriateness of aquatic exercise program. In that, the policies and procedures should be specified basis of the precautions and contraindications [1, 12]. Some of the special precautions and contraindications include the following:

• Fear of water (water phobia)

• Neurologic disorders

• Uncontrolled Seizures

• Cardiac/respiratory dysfunction

• All infections and open wounds

• Contagious skin rashes

• Kidney disease (inability of urine output)

• Chlorine or bromine allergy

• Unstable blood pressure

• Uncontrollable bowel/bladder

• Non-tunnel catheters

• Epilepsy (problems with glare)

• Aspiration

• Severe impulsivity

• The danger of bleeding or hemorrhage

4.1 Warning signs

It is important to monitor the obese individual either during exercise time, or while they relax at a normal water temperature. It is not only essential to start the aquatic exercise program with 50–55% of intensity, but the below warning signs are always considerable during each session:

• Light-headedness

• Nausea

• Headache

• Dizziness

• Increased pain

• Agitation

• High fever

5. Aquatic exercise as fitness and weight loss program

While a variety of physical activity and exercise program has provided health and weight management program, in the past four decades, aquatic exercise training became an alternative and favorable program for fitness and rehabilitation purpose for obese or people who have physical difficulty exercising on the ground [9]. In addition, proper breathing technique consists of controlling time of inhale, exhale, and holding breath during exercising significantly improve the capability of cardiorespiratory fitness (CRF) and some cardio metabolic biomarker [17]. While the risk of cardiovascular disease increases progressively when blood pressure (BP) indicates above 115/75 mmHg [18] among obese people, water-based exercise is as an effective method of physical activities and exercise to decrease stress and high blood pressure [19, 20].

Typically, water applies as a resistance for similar exercises that normally are done on land, such as jogging or jumping jack. It is mostly performed with individuals who are not skilled in swimming strokes. Additionally, aquatic exercise offers equal benefits as other types of exercise, but it provides a lower risk of injuries to the muscles and joints while recovering cardiorespiratory fitness, muscular fitness, body composition, agility, flexibility, and also blood lipids in obese populations and older adults [12].

Besides, water-based exercise, also called aqua aerobics, aqua exercise, aquatic dance exercise, water workouts, or hydro aerobics, is an activity that can leave participants feeling exhilarated. Water exercise often performed to music, provides a workout for the heart and lungs, as well strengthening and toning muscles [11]. It is obvious that being free from the effects of gravity makes movement easier in water. Interestingly, anyone can have fun in a water exercise class. Individuals do not have to be able to swim and do not need previous experience to achieve success. Some aquatic classes use music during the workout. Obese participants in water aerobics classes (at least 30 minutes) can effortlessly burn about 300 calories. Many workouts in the aquatic classes include stretching exercises, kicking, jumping, squats, dance movements and warm-ups, a cool-down or relaxation period.

Aquatic aerobics exercise is commonly more low-impact than land-based exercises, while participants have higher energy expenditure due to the resistance of water. Also, movements tend to perform with slower speed because of the water viscosity.

5.1 Aquatic aerobics exercise programs

Aquatic aerobics exercise, as one of the modern forms of exercise, is becoming more and more popular among the public, specially for obese women. It is a type of resistance training in the water. Aqua aerobic exercise supports the body weight to reduce the risk of injury to the joints and muscles. During stretching the legs in the water, the buoyancy force gives less stress on the joints, which allowed maximum range of motion in water. Aquatic exercise can also improve physical and mental health and overall, the quality of life.

In any aquatic program format, all elements of the program including the needs and abilities of participants, the purpose of the session, the size and shape of the pool, equipment availability, water temperature, and the environment must be considered. According to the American College of Sports Medicine [21] recommendations, the components of training sessions for aquatic exercise are also included a warm-up, conditioning or specific sport-related exercise, and finally stretching and relaxation as a cool-down [1, 11].

Warming-up: An aquatic exercise session warm-up involves a thermal warm-up, pre-stretch, and cardiorespiratory activity continuing at a minimum of 5 minutes. This section will be instructed in a variety and creative ways based on the specific objectives of the aquatic program.

Conditioning phase: in general, the conditioning phase consists of the primary exercise mode such as cardiorespiratory or aerobic training, muscular strength and endurance, stability, flexibility and neuromotor exercise. A conditioning phase in any session can purposively be the combination of these exercise modes.

Cooling-down: Even though, cooling-down can be optional in a session of aquatic exercise, in most aquatic fitness programs, it still consists of two parts including the cardiorespiratory cool-down and the post-stretch. In this part, stretching, deep breathing technique, relaxation movement and self-care and free activity in the water also can usefully be recommended.

5.2 General recommendations

Even though water is a lenient and versatile exercise medium, sometimes older adults, elderly, and obese people will not able to safely perform movements exactly as instructed or intended. Then, the participants’ ability, the movement purpose, the class purpose, and the modifications possibility or optional movement should be considered when planning aquatic exercise programs. Using general recommendations for any section of the class and various formats can be attractively designed to keep aquatic classes engaging, provide training variety and motivate obese participants. Therefore, to get started and adhere to aquatic exercise till the ideal weight the following are suggested:

• Exercise with music

• Listen to your body respond

• Take time to conduct periodic assessments

• Record your activities regularly

• If any health problem arises, visit a physician

5.3 Programming considerations

• Safety

  Steps, ramps, and ladders may serve as access for safe entry and safe exit at the pool. Participants should be reminded to wear shoes and be aware of clothing to prevent slips or falls and chafing.

• Programming

  Exercises that cause discomfort shall be avoided, specifically for those with musculoskeletal considerations, who might need to have an alternative program with low-impact intensity in shallow water. However, to plan an appropriate aquatic exercise program the below factors are considerable:

• Leadership skills

• Suggest the option of wearing aquatic that makes them feel more comfortable.

• Equipment and the knowledge of the usage of each aid-assistant. For example, drag resistance is most suitable for training progression and buoyancy resistance like hand bars may compromise body control.

6. Aquatic exercise guidelines

6.1 Aquatic exercise prescription

According to ACSM [21], a reduction of 3–10 percent of initial weight over 3–6 months by an aerobic exercise program at a moderate intensity level with resistance training is recommended. Then, obese people need to do exercise a minimum of 5 days per week. In other words, the goal of weekly exercise activity should be 300 minutes per week, or approximately 60 minutes per day to burn 500–600 kcal as shown in Table 2 [1, 7].

Intensity	Type	Frequency & duration	~kcal	Example of movement
Low to moderate- with resistance	Aerobic interval (1:1 ratio)	3 sessions weekly, 60 minutes	500–600	2 minutes of hard skier jumping jack extension (work): 2 minutes steady wide walk/jogs (recovery)

Table 2.

A summary of aquatic exercise prescription.

6.2 Aquatic exercise intensity

It is essential to monitor aquatic exercise intensity levels to achieve a significant weight loss result. In addition, the ACSM [21] guidelines advise obese people to start aquatic exercise somewhat easily and continue the workout with moderate exercise for a long time. Based upon the Borg Rating of Perceived Exertion (RPE) the Aquatic Exercise Intensity Scale for weight loss purposes is recommended as below:

Start with ~50–55% Aquatic HR: Somewhat easy RPE level. At this intensity level, you feel that you can continue exercising for hours. You can still easily speak in full sentences and have conversations while the breathing and heart rates are slightly increased.

Continued with ~60–65% Aquatic HR: Moderate RPE level. At this intensity level, you could do the exercise for a long time. Your breathing and heart rates will noticeably start to rise. Your body is sweating, which reminds you of going beyond a normal exercise level as the muscles feel contractions and start working. Then, at this level, you could continue the activity for a while before having to rest or stop. The proper example to compare this moderate intensity is a brisk walk or like walking up a slight incline. In this condition, you are still able to say four to five words before taking a breath [1].

6.3 Determination of aquatic heart rate

Firstly, stand out of the pool for 3 minutes, and after that determine the heart rate (HR) for 1 minute. Then, similarly, determine a one-minute HR after 3 minutes of standing in the water (submerging at the axillary level of depth). The aquatic HR is determined by subtracting the standing HR in the water from the standing HR out of the water. It should be mentioned that this deduction will be used via the Karvonen formula to determine the target heart rate [1].

However, it is obvious that environmental conditions, medication, caffeine, excessive activity, or unnecessary movement can affect heart rate response once entering the pool. Then, proper supervision should be considered to minimize these factors [11]. However, important factors that influence aquatic exercise Heart Rates (HR) are shown in Table 3. In that, carefully applying a proper heart rate is always advisable.

Factors	Effect
Water temperature	Water is more efficient to cool the body than air. This cooling reduces the impact of heat stress during exercise and allows lowered heart rate response. Then, cooler aquatic media does not allow the heart to work as hard to drive out the produced excess heat during exercise.
Gravity	The water buoyancy lessens the gravity effect on body mass.; Bloodstream from extremity limbs assists the heart with less effort, resulting in a lowered heart rate.
Compression	Water acts on all body systems (vascular system) such as compressors and it causes a reduced venous load to the heart than equivalent land-based exercise. In that, the heart with lesser working returns blood from the extremities.
Partial pressure	A molecule of gas under pressure more readily enters a liquid. Oxygen is a gas and blood is a liquid. So, a gas transfer might occur more efficiently due to the pressure of water. This better gas exchange results in a reduction of the requirement of increasing heart rate and bloodstream and finally leads to a lesser workload for the heart.
Hydrostatic pressure and immersion	While an individual horizontally floating (prone or supine position), hydrostatic pressure aids in returning fluid and blood to the heart and lymphatic fluid return. It also makes lower working heart rate and affects respiration (HR is 13–17 bpm on average lower in the water) which consequence in increased vital capacity.
Reduced body mass	Since you weigh less in the water, a reduction in body weight might be partly responsible to have lower aquatic HR.

Table 3.

Influence factors on aquatic heart rates (HR) during exercise.

6.4 Immersion level

The buoyancy of the water not only allows it easily to modify high-impact activities, but the immersion in water also reduces the risk of side movements. It also supports weight for single-limb activities which are too challenging on land. Weight-bearing is affected by the depth of water owing to buoyancy as well. In general, for obese participants, immersion level is recommended on the xiphoid and the anterior superior iliac (ASIS) level with approximately 25% of the body weight [12].

6.5 Water temperature

The water temperature range is suggested to be set between 27 and 30°C (80–86°F) for overweight and obese participants as well as the tempo of the exercise [9].

6.6 Aquatic program formats

• Circuit training:

  Circuit training is often an instructor-guided program referred to as station training with any combination and various stations.

• Interval training:

  Interval training is implicated in a series of training cycles where the ratio of work–rest sets the basis for training.

• Dance-oriented programs:

  The dance-oriented program includes A variety of dance classes with specific styles of dance, like hip-hop, ballet, ballroom, or traditional and ethnic rhythms dances.

• Stride training (Walk and Jog):

  Stride training can be designed through striding patterns such as forward and backward walk/jog, and sidewalk/jog. It is also incorporated in different water depths as a warm-up or cool-down format for other aquatic exercise programs also. Walking and jogging training is carried out on treadmill, also.

• Aqua cycle program:

  Aqua cycle program or aquatic cycling can be designed with a circuit-training workout or interval training for the improvement of cardiorespiratory fitness. Aquatic cycling can also focus on muscle conditioning also.

• Aqua-step:

  An aquatic step program can be set up for the improvement of cardiorespiratory training, muscular fitness, or neuromotor activities. A step (a proper bench or a platform) to step up and down is needed during a class.

• Aqua-pole:

  Aqua-Pole exercise format can focus on various health, fitness and rehabilitation protocols. The training program is designed to improve not only overall fitness, but posture, muscular strength, and toning, and also included choreographic techniques to challenge agility, coordination and cardiorespiratory endurance.

• Aqua-trampoline:

  Mini trampoline as the elastic nature can offer for unique workout at a low-impact exercise option in water media. In addition, during all movements core muscles need to actively be involved since trampoline surface is unstable.

• Muscular conditioning programs:

  This type of training focuses mainly on muscular fitness. It is also offered as a station of a circuit training program for muscle conditioning with specific segments.

• Martial arts programs:

  Martial arts–style classes are performed by assigning movement patterns and techniques such as kicks, punches, and blocks into the water. It is carried out with a high-intensity, highly resistive, while it is still an option with a lower-impact exercise [1].

7. Summary

The aquatic exercise program is a non-weight bearing exercise that increases energy expenditure while the body is immersed in water. Aquatic exercise not only can be recommended as a desirable body composition and weight loss for obese people but as an overall health-related fitness component, also. Water-based exercises, specifically aquatic aerobics, can easily help to promote fat loss. As well, the body can build lean tissue or muscle mass while working against the three-dimensional resistance of the water (viscosity). The most effective aquatic exercise program formats for weight loss are comprised of striding (walking/jogging) in shallow or deep depths of water, aquatic step, martial arts style, aquatic dance, aquatic cycling or spinning, and circuit and interval training in shallow water. The training sessions include warm-up, conditioning, stretching and relaxation as a cool-down. The immersion level is mostly recommended on the xiphoid level with approximately 25% of the body weight and the water temperature should be set between 27 and 30°C. For all aquatic exercise programs, obese people should preferably exercise a minimum of 5 days per week for 60 minutes per day at a moderate intensity level with resistance training. Carefully determining aquatic heart rate in order to exercise with an appropriate heart rate and moderate intensity is always advisable. Considering the advantages of aquatic exercise programs, the limitations and potential risks for obese people also should be determined and all special precautions and contraindications need to be thought out.