Cardiovascular Endurance and Spatial Orientation - Essay Example

What is Cardiovascular Endurance Cardiovascular endurance has come to refer to a high level of aerobic fitness, which is maintained by persistent activity. It is the heart and lung's ability to pump oxygen to working muscles allowing a person to accomplish even strenuous activity throughout the day without much fatigue. As noted: 'Nutrition and fitness guru Dr. Phillip Maffatone considers endurance to be "a steady state level of activity where one can develop and sustain relatively high speeds at a sub maximum effort over time; the ability to develop higher speeds while remaining predominately aerobic; increasing the percent fat burning and decreasing the dependence on carbohydrate utilization with training."' (qtd. in Elliot) Types There are broadly four types of endurance. Given below is a brief description of each: 1. Aerobic endurance: Aerobic means 'with oxygen'. During aerobic work the body is working at a level such that the demand for oxygen and fuel can be met by the body's intake. The only waste products formed are carbon dioxide and water. These are removed as sweat and by breathing out. Aerobic endurance can be sub-divided as follows: Short aerobic - 2 minutes to 8 minutes (lactic/aerobic) Medium aerobic - 8 minutes to 30 minutes (mainly aerobic) Long aerobic - 30 minutes + (aerobic)" (Endurance Training) 2. Anaerobic endurance: Anaerobic work refers to a very high level of effort exerted by the body. So much so, that the demand on the body to produce oxygen and fuel is so great that supply falls short. In such circumstances the muscles use stored reserves of fuel to produce energy. Anaerobic endurance is further sub divided as follows: Short anaerobic - less than 25 seconds (mainly alactic) Medium anaerobic - 25 seconds to 60 seconds (mainly lactic) Long anaerobic - 60 seconds to 120 seconds (lactic +aerobic) 3. Speed endurance: This is important to develop coordination of muscle contraction. 4. Strength endurance: This aids the development of muscle quality and its contractile force. Why is Cardiovascular Endurance Important If one does nothing at all then only a small amount of energy is required for sustenance. This is the basal metabolic rate (BMR). Anything done over and above this - any exercise or movement- requires extra energy and the body needs to be able to provide for this. Given this context, one cannot overemphasize the importance of cardiovascular endurance. It is crucial to produce that extra energy. It is what gives one stamina. Without cardiovascular endurance one may always experience a state of exhaustion. Cardiovascular endurance has a direct relationship with the aerobic system. The stronger the cardiovascular endurance, stronger is the aerobic system and vice versa. When the aerobic system is efficient then the body need not use the anaerobic system of energy production which increases lactic acid causing the muscles to become more acidic, work less efficiently and imparts muscular pain that is associated with exercising hard. According to Evans, M.: "the more energy we can get from the aerobic system, the less we need from the lactate-producing anaerobic system, and training the anaerobic system may also increase the threshold through improved buffering and removal of lactate."(9).Thus, a high level of cardiovascular endurance helps draw on the aerobic system for energy and avoids the accumulation of waste products, the chief one being lactic acid. While cardiovascular endurance is important for those involved in a high level of physical activity it is especially important for sportsmen and even more so for athletes. Limitations There are eight elements the lack of which can interfere with cardiovascular endurance. These are: 1. Lack of strength which interferes with muscle contraction against resistance 2. Lack of power, which will not allow muscular contraction when sudden movements happen. For eg. Jumping or sprint starting 3. Low agility will impede performance of explosive power movements in continuous pattern in opposing direction. For eg. Zig zag running or cutting movements. 4. Lack of balance will obstruct the body's ability to stay in a certain position either while standing which is seen in handstand or while moving which can be required in a gymanst's move. 5. Poor flexibility hinders the ability to achieve an extended range of motion because of excess tissue, i.e. fat or muscle which may be required for executing a leg split 6. Lack of local muscle endurance will impede a single muscle's ability to perform sustained work for eg. in rowing or cycling. 7. Lack of strength can hamper the muscle's ability to perform maximum contracture, time and again. 8. Lack of coordination will not allow all the above listed components to integrate in a way so that effective movements are achieved. Examples Some of the best examples which help improve cardiovascular endurance are running, jogging, aerobic dance, cycling (spinning) and walking. How to Improve Cardiovascular Endurance To improve cardiovascular endurance non stop exercise at target heart rates, usually for 20- 30 minutes at 4 times a week. The activity must increase the heart rate to 70-80% of its maximal potential to see any visible improvement. This would imply a pulse rate between 130-170 beats per minute. Optimum benefits are achieved if the heart rate can be maintained at the consistent level throughout the exercise period. There are three interrelated training factors which can improve cardiovascular endurance : frequency, intensity, and duration. Among these intensity is the most critical to improvement of cardiovascular endurance Some examples to improve each type are given below: 1. For aerobic endurance continuous and interval running is suggested 2. For anaerobic endurance repetition methods of high intensity work 3. Speed endurance is enhanced with competition and time trials. Repetition methods are used with a high number of sets, low number of repetitions per set and an intensity greater than 85% with distances covered from 60% to 120% of racing distance. (Endurance Training) 4. Strength endurance is achieved through circuit training, weight training and hill running. Cardiovascular Endurance Exercise as it Relates to Children Whether children should perform adult type endurance training has often been discussed. The approach is to provide such training to children with modifications in type and intensity of training to improve VO2 max (the maximum amount of oxygen in milliliters, one can use in one minute per kilogram of body weight). "In general, the research shows that if children follow a 3 to 5 times a week routine of at least 20 minutes continuous activity for 12 weeks, then improvements in VO2max of 7 to 26% is possible. On average, though, and the results of some of the better-controlled experiments support this, a child can expect a 10% improvement in VO2max after following an 'adult-like' CV training programme. The consensus from the research is that children can improve their aerobic fitness but not to the same degree as adults, when following a similar training programme." (Coaching Young Athletes). Due to a hormonal trigger Cardiovascular trainability is limited till puberty. A child's heart is smaller than an adult's therefore the amount of blood the heart can pump with one beat is lower in children heart and can limit additional improvement in VO2 max. What is Spatial Orientation Levy describes spatial orientation as "the ability to comprehend static or stationary objects"(front matter).Spatial orientation is also defined as "our natural ability to maintain our body orientation and/or posture in relation to the surrounding environment (physical space) at rest and during motion"(Antunano,1). It is that dimension of the intellect, which imparts one with the ability to think in various dimensions and fit thoughts based on mental maps. The three primary sources of spatial orientation are: 1. Vision: It relates the orientation of the body to an externally fixed frame for reference. When visibility is strong vision governs spatial orientation 2. The equilibrium sense (the otoliths) which assumes that the G force is vertical which is not the case when flying takes place 3. Proprioception (receptors located in the skin, tendons, muscles and joints) which also relies on the G force Spatial orientation is the ability to comprehend an arrangement of elements within a visual stimulus pattern and stay focused despite variations in an object's orientation. Why is it Important Spatial orientation is extremely important in flight situations and especially for pilots. The way human body functions, it maintains spatial orientation on the ground but when off the ground it tends to lose it. That turns out to be a situation when orientation really needs to be maintained to avoid sensory conflicts and illusions created by three-dimensional environment of the flight, which is not familiar to the human body. Many aviation accidents are attributable to a lack of spatial orientation. Limitations Low visibility can hamper spatial orientation. When visibility is bad while flying, the otoliths and proprioception take over spatial orientation causing illusions and misjudgement. The numerous sensory stimuli (visual, vestibular-organs of equilibrium located in the inner ear, proprioception) differ in magnitude, frequency and direction. Any discrepancies in visual, vestibular, proprioception sensory inputs can cause illusions and result in spatial disorientation. Without effective perception, integration and interpretation of visual, vestibular, proprioception loss of spatial orientation is most likely. The vestibular system consists of the semicircular canals ion the middle ear and monitors the position of the body in space, while the proprioceptive system consists of many different sensory receptors in the muscles, tendons and ligaments that monitor the position of body parts relative to the body. The sense of vision and the ability/inability to focus may impact the success of spatial orientation. Similarly, injuries involving muscles, tendons, and ligaments will impact spatial orientation. Any disturbance in the connection between the vestibular system and eyes can disturb balance and focus of the eyes, when the head is moving or body is rotating. The semicircular canal also impacts spatial orientation. For example when the head is straight in the airplane the fluid in the canal does not move and hair do no stand up signaling the brain that there is no turn or rotational acceleration. But when the head does turn in the aircraft and continues to do so for more than 20 seconds, the fluid inside the canal begins to move and friction can cause it to catch up with the walls of the rotating canal. This can cause the hair to return to straight position signaling the brain that head is not moving when it actually is. Examples The best example of spatial orientation is a situation when one loses it. This happens most often when there is change in gravity for example when there is a vertical take off by helicopter or a sudden opening of parachute after a free fall. How to Improve Spatial Orientation The best way to improve spatial orientation is by measuring it and then simulating an environment by way of virtual reality to enhance it. As pointed by Allahayr and Hunt "visual-spatial ability has been identified as one of the primary factors of intelligence. Numerous tests, including paper-and-pencil tasks and laboratory experiments, have attempted to provide an accurate measure of this ability. However, the majority of these tests serve only as surrogate measures of visual-spatial ability and may not provide a precise prediction of the individuals' performance in a real environment.[] we introduce the use of virtual reality (VR) or virtual environments (VEs) as a new method to measure human spatial orientation"(263). For example use of visual cues which focus on optic flow in conjunction with proprioceptive and vestibular cues especially if reference points (landmarks) are missing can help measure and improve spatial orientation. Using virtual environment as a training tool can help enhance spatial abilities. One of the ways to improve spatial orientation is to improve spatial comprehension which like verbal comprehension involves ability to perceive, understand, remember, and recall for future use. For pilots the suggested method for improving spatial orientation is: Getting control on spatial disorientation by experiencing disorientation illusions in a Barany chair, a vertigon, a GYRO,or a virtual reality spatial disorientation demonstrator Improving competency in airplane with reference to instruments especially when visibility is low When experiencing vestibular illusion it is advisable to trust instruments rather than perceptions. Spatial Orientation as it Relates to Children Psychologists have tried to establish the kind of information children use when orientating in new environments, if given proximal and distant landmarks, and how spatial memory develops in the age groups of 5, 7 and 10 year old children. Lehnung M. et al. conducted a study where children of these age groups "were presented with the 'Kiel Locomotor Maze', containing features of the Radial Arm Maze and the Morris Water Maze, in order to assess spatial memory and orientation. Children had to learn to approach baited locations only. Task difficulty was equated with respect to the children's age. Training was given until the children reached criterion. During testing, the maze configuration and response requirements were systematically altered, including response rotation, cue rotation, cue deletion and response rotation with cue deletion in order to assess the spatial strategies used by the children. During training and testing, working-memory errors (WM), reference-memory errors (RM) and working-reference memory errors (WR) were recorded. As expected, no difference between age groups appeared during training, thus confirming comparable task difficulty across age groups. During testing, age groups differed significantly with regard to the orientation strategy used. The 5-year-olds were bound to a cue strategy, orientating towards local, proximal cues. The 10-year-olds mastered all tasks, thus displaying a place strategy, being able to use distal cues for orientation, and were even able to do so after being rotated 180 degrees. The 7-year-olds proved to be at an age of transition: five of them were bound to a cue strategy, five children were able to adopt a place strategy. The differences in the orientation strategies used by children of different age groups was reflected by the sum of errors they made, also by RM. WM were found to be rare, especially in older children. We conclude that preschoolers use a cue strategy, that the development of place strategies occurs during primary school age and seems to be complete by the age of 10 years" Review Quiz 1. What can impede cardiovascular endurance 2. How can one improve cardiovascular endurance 3. What are the sources of Spatial Orientation 4. In what situations does one become spatially disoriented Works Cited Allahyar, M. Hunt ,E. "The Assessment of Spatial Orientation Using Virtual Reality Techniques". International Journal of Testing. Vol. 3, No. 3(2003): 263-275 Antunano, M.J. "Spatial Disorientation." Medical Facts for Pilots. Federal Aviation Administration.Oklahama.Publication:AM-400-03/1:1-10 Coaching Young Athletes. 21 Aug 2005. Sports Coach.< http://www.brianmac.demon.co.uk/articles/scni4a5.htm> Elliot,B. Health & Fitness:Cardiovascular Endurance.2000.Adirondack Sports & Fitness.15.10.05. Endurance Training. 1 Jan. 1997.Sports Coach.17 Oct.2005< http://www.brianmac.demon.co.uk/enduranc.htm> Evans, M. Endurance Athlete's Edge. USA: United Graphics, 1997 Lehnung, M. et al. "Development of spatial memory and spatial orientation in preschoolers and primary school children" British Journal of Psychology. (1998):463-80 Levy, Joan. Mechanical Aptitude & Spatial Relations Test (Mechanical Aptitude and Spatial Relations Tests).USA:Thompson Peterson's. 2004. Read More