Introduction
The relationship between physical activity and health has been confirmed for all ages (24 12
Hearing loss, apart from problems related to communication and perception of sound stimuli, does not produce kinetic or intellectual problems, and consequently, it should not be considered as a cause for excluding individuals with hearing loss from physical activity involvement (3
Development of physical abilities provides individuals with hearing loss the possibility of participating in athletic activities along with individuals with typical sense of hearing, consequently acquiring relative social profits (2 21 23
Researchers (7,19 2 max) reported in favor of children and adolescents with typical sense of hearing compared to peers with hearing problems (26 27 2 max of individuals with hearing loss create the necessity for motivating their attendance in systematic physical activity.
A number of studies (1,4,16,25 6,15 aerobic capacity of individuals with hearing loss compared to individuals without hearing problems; hence, an adapted exercise program could probably improve these levels.
Dance is one of the activities that contribute significantly to the growth of physical and psychological abilities of individuals with typical sense of hearing (14 exercise . Dance's advantage is that music gives a pleasant note during practice and is considered as an important motivation factor for the maintenance of intensity that leads to physical adaptations (20
The Greek traditional dances include elements such as the alternation of intensity and the variety of rhythm and speed. Interval method is the method mostly applied during practice, providing dancers the opportunity to recover between songs and to receive corrections from the instructor. At the same time, implementation of steps and particularly dancing figures requires eccentric (plyometric) and concentric (myometric) contractions. Because for individuals with hearing loss no additional restrictions are observed apart from communication problems during physical activity, it is likely that participation in traditional dance programs will cause adaptations in their physical fitness level.
Reviewing the literature, it is evident that the positive effect of dance programs on the physical fitness of individuals with typical sense of hearing has been verified (5,9,10,18,22
Methods
Experimental Approach to the Problem
In this study the sample consisted of 23 adults with congenital hearing loss, all living with their parents, assigned to 2 groups of 10 and 13 subjects, for the control and intervention group, respectively. Data collection methods included premeasurements and postmeasurements of cardiovascular fitness and muscle strength for all participants of both groups. Premeasurements were used for participants' separation in 2 groups with the medium averages for the control and intervention group, respectively, in each cardiovascular fitness and muscle strength variable being approximately equal, ensuring in this way that both groups started from the same reference point prior to the application of the program. The intervention group received a 12-week traditional dance training program directed toward improving the cardiovascular fitness and muscle strength of its participants.
Prior to the start of the intervention program, a preintervention phase of 2 months was preceded to familiarize participants with the steps of each dance implemented in the program, with a view to release stress of the individuals so as to practice with the desirable levels of intensity during the intervention phase. Similarly, the holistic approach of communication was used to eliminate the probability of incorrect comprehension and performance of dances. Table 1 presents the names, intensity, and duration of traditional dances that were included in the intervention program.
Table 1: Greek traditional dance program.
The intervention group followed a 12-week traditional dance training program, at a frequency of 2 training sessions per week for 90 minutes each session. All participants wore athletic shoes and sport clothes during each session. All adults with hearing loss did not participate in other training programs during the research.
No subject of the intervention group was absent for more than 2 training days. The training program was designed to include exercise with the form of traditional dances applying the interval method with small periods of rest between the activities, while exercise intensity was alternating as a result of dances' alternation of rhythm. Auditory stimuli were strengthened with the use of a percussion instrument called “ntaouli” played at the center of the participants' circle by the teacher, who was also the program instructor, so as to help individuals with hearing loss to perceive vibrations transmitted to their bodies. At the same time, two adult dancers with typical sense of hearing participated in the intervention program to provide visual feedback to individuals with hearing loss.
Initially, 12 dances of Thrace origin were executed, followed by 7 dances of Macedonia origin. Between dances, a short rest period of about 10-15 minutes was included, and in the middle of each session a 5-minute rest period was given.
The training seasons took place in an indoor municipal gymnasium. Telemetry (Polar Vantage NV HRM, Polar Electro, Finland) was used for every training session on all participants to record heart rate and define the medium average of intensity in each dance according to maximal heart rate, measured at the first laboratory maximal test by means of an electrocardiograph.
Control group adults, although they did not participate in the traditional dance training program or any other sport or physical activity, underwent the same measurements as the adults of the intervention group.
Subjects
The sample of this study consisted of 23 adults (11 men, 12 women) with hearing loss, all coming from the Union of the Deaf of Northern Greece (UDNG). Information regarding level of hearing loss of the individuals was derived from the official files of UDNG. Subjects were assigned to 2 groups (control and intervention) according to their desire to participate or not to participate in the traditional dance training program. Consequently, 13 adults (6 men, 7 women) with hearing loss (mean age, 25.7 ± 3.9 years; mean height 168.8 ± 8.8 cm; mean weight 70.4 ± 16.1 kg; level of hearing loss >83.0 ± 9.9 dB) constituted the intervention group, whereas 10 adults (5 men, 5 women) with hearing loss (mean age, 26.4 ± 5.9 years; mean height 166.9 ± 9.6 cm; mean weight 69.6 ± 19.2 kg; level of hearing loss >85.0 ± 6.2 dB) constituted the control group. Participants of both groups exercised occasionally for recreational reasons.
All individuals with hearing loss did not have any history of cardiac problems, metabolic diseases, and orthopedic problems that could interfere with walking or running and were not undergoing medication treatment that could alter their heart rate or metabolic responses to exercise . Each individual of this sample was informed of the purpose of this study and its experimental risks and procedures. All participants signed an informed consent document prior to the investigation, which had been approved by an Institutional Review Board for use of human subjects.
Testing included the evaluation of oxygen uptake, minute ventilation (E ), respiratory exchange ratio (RER), and measurement of peak torque before and after participation in the training program for the participants of both groups.
Procedures
All measurements were conducted at the Department of Physical Education and Sport Science, Aristotle University of Thessaloniki. Prior to the measurements, subjects were informed and familiarized with the laboratory environment and equipment and its operation and the protocol of the research through 3 familiarization sessions, with a purpose to give participants sufficient time to practice and to provide an environment in which each subject considered himself or herself a cooperating member.
Clinical examination and measurement of physical characteristics of the individuals took place at the Laboratory of Developmental Pediatrics and Special Education, whereas aerobic capacity evaluation and isokinetic muscle strength measurement were conducted at the Laboratory of Ergophysiology-Ergometry. Testing for the participants of both groups included 2 measurements (initial and final) prior and after application of the training program.
Two examiners, both familiarized with equipment operation and testing procedures, conducted all measurements. The research protocol took place during 2 separate days of testing spaced 48-72 hours apart. As the results showed, there was a high reliability (r > 0.90 based on intraclass correlation coefficient between the 2 measurements in terms of aerobic capacity and isokinetic muscle strength . Therefore, the design of the study incorporated the estimation of the highest performance of each subject and the better of the 2 efforts for each parameter was chosen for data analysis.
Aerobic Capacity Prior to actual testing sessions and for 3 days participants were familiarized with the laboratory and taught to run or walk comfortably on a motorized treadmill (Jaeger LE 6000, Wurzburg, Germany). During this session, instructions concerning test procedures and a test demonstration were provided to participants with the use of a holistic method that included lip reading, sign language, and finger spelling, without participants receiving any auditory stimuli. All tests were conducted at temperatures ranging from 22° to 25°C. The starting speed for the maximal graded treadmill test was individualized for each participant. Exercise testing was repeated twice, at separate days, to ensure reliability of testing scores. Heart rate and systolic and diastolic pressures were measured before exercise . Heart rate was measured by means of an electrocardiograph (Hellige, Germany), whereas blood pressure was measured by means of the indirect auscultation method using a sphygmomanometer.
Based on our pilot study and the familiarization period, a treadmill test protocol was designed for participants. Individuals began walking at an initial speed of 4 km/h−1 for 4 minutes, increased to 6 km/h−1 for 2 minutes with a grade of 1%, then incrementally increased by 1 km/h−1 every minute and a constant grade of 2% was maintained throughout the rest of the test until volitional exhaustion.
Oxygen uptake, E , and RER were determined using an open-circuit spirometry system (Jaeger EOS-Sprint, Wurzburg, Germany) as described earlier (17 exercise tests. Metabolic data were calculated and displayed in 30-second averages. The criteria for attainment of peak oxygen uptake (O2peak ) were a plateau in heart rate (HR) with an increase in workload and a respiratory exchange ratio higher than 1.1. The total time of all tests was recorded.
Muscle Strength The peak torque values of knee extension and flexor were measured on a Cybex II isokinetic dynamometer (Lumex Inc., Ronconkoma, NY, USA). The isokinetic peak torque of hamstring and quadriceps muscles was measured at angular velocities of 60°/s−1 , 180°/s−1 , and 300°/s−1 .
During testing, instructions given were the same for each subject using the holistic method of communication so as to avoid the effect of external or internal motivation.
Statistical Analyses
The data were analyzed using the Statistical Package for Social Sciences version 14 (SPSS Inc., Chicago, IL, USA). Repeated measures of multiple analyses of variance (2 × 2 ) were used to test mean differences between the values of both groups. Statistical power was included to determine whether the power related to sample size and effect size was adequate. A paired t -test was used to compare the values within each group before and after participation in the program. Significance was set at 0.05 (p ≤ 0.05).
Results
No significant differences between participants in terms of age, height, and weight were indicated by the t -tests. Peak HR and peak RER were not significantly different. The groups had similar pretraining and posttraining values regarding all metabolic measures and treadmill performance.
Following training, the intervention group improved peak E : F (1,12) = 7.070, p < 0.05, p = 0.90, n 2 = 0.32, O2 peak: F (1,12) = 4.939, p < 0.001, p = 0.77, n 2 = 0.25 for absolute and F (1,12) = 5.829, p < 0.001, p = 0.84, n 2 = 0.28 for relative peak, and test time: F (1,12) = 17.558, p < 0.001, p = 1.00, n 2 = 0.54, compared to their baseline scores. The control group showed no changes after the 12-week period [peak E : F (1,9) = 2.549, p = 0.30, n 2 = 0.22, O2 peak: F (1,9) = 0.134, p = 0.06, n 2 = 0.01 for absolute and F (1,9) = 0.001, p = 0.05, n 2 = 0.01 for relative peak, and test time: F (1,9) = 0.073, p = 0.06, n 2 = 0.008]. Table 2 presents descriptive statistics for peak HR, RER, E , O2 peak (absolute and relative), and test time prior to and after the application of the program.
Table 2: Respiratory and metabolic responses during maximal treadmill exercise test prior and after 12 weeks of training.
Concerning muscle strength , no statistically significant differences were found between the 2 groups before and after the application of the intervention program.
The isokinetic peak torque of anterior femoral muscles at angular velocities 300°/s−1 [F (1,12 p < 0.001, p = 0.84, n 2 = 0.28], 180°/s−1 [F (1,12) = 1.573, p < 0.05, p = 0.31, n 2 = 0.09], and 60°/s−1 [F (1,12) = 3.398, p < 0.05, p = 0.59, n 2 = 0.18] was significantly improved as the comparison between the 2 measurements (initial-final) reveals for the intervention group. Similarly, postintervention measurements showed a significant increase of isokinetic peak torque values of posterior femoral muscles at angular velocities 300°/s−1 [F (1,12) = 8.584, p < 0.001, p = 0.95, n 2 = 0.36], 180°/s−1 [F (1,12) = 6.305, p < 0.001, p = 0.86, n 2 = 0.30], and 60°/s−1 [F (1,12) = 4.539, p < 0.05, p = 0.73, n 2 = 0.23] compared to preintervention measurements.
On the contrary, no statistically significant differences were noticed for the control group between the 2 measurements of anterior femoral muscles at angular velocities 300°/s−1 [F (1,9) = 2.953, p = 0.34, n 2 = 0.24], 180°/s−1 [F (1,9) = 0.927, p = 0.14, n 2 = 0.09], 60°/s−1 [F (1,9) = 1.687, p = 0.26, n 2 = 0.06] and posterior femoral muscles at angular velocities 300°/s−1 [F (1,9) = 2.715, p = 0.31, n 2 = 0.23], 180°/s−1 [F (1,9) = 5.118, p = 0.52, n 2 = 0.36], 60°/s−1 [F (1,9) = 4.484, p = 0.47, n 2 = 0.33].
Descriptive statistics regarding isokinetic peak torque of quadriceps and hamstring femoral muscles before and after program application are presented in Tables 3 and 4 , respectively.
Table 3: Pre-post values of peak torque (Nm) of quadriceps muscles.
Table 4: Pre-post values of peak torque (N·m) of hamstring muscles for experiment group and control group.
Discussion
The aim of this present study was to investigate whether a traditional dance training program could improve the physical fitness of adults with hearing loss. Although adults participated in this program according to their desire, that seemed to have no influence on the pretraining results because both groups had similar pretraining values in terms of metabolic measures, treadmill performance, and peak torque of knee extension and flexion.
The results of this study showed that the application of a traditional dance training program with a medium average intensity at 74% of HR peak, 2 times/week, for 12 weeks was effective in enhancing aerobic capacity of adults with hearing loss. The treadmill test of cardiorespiratory efficiency provided a direct measure of the physiological effects of the training program. A finding provided was that the average heart rate for individuals in the intervention group just before pretest and posttest measurements did not differ significantly. However, response of individuals' cardiorespiratory system during the posttraining treadmill test indicated that adults significantly improved their capacity to perform continuous and sustained work. The program was applied at a frequency of 2 times per week, a fact that corresponds to actual situation because most traditional dance groups participated 1-2 times per week. However, it is very likely that if the frequency of program was more than 2 times per week, then the improvement of physical abilities of this study's participants would increase in higher levels.
This study takes into account that outdoor and laboratory trials that attempt to estimate cardiorespiratory fitness and muscle strength , especially of untrained subjects, can be affected by factors such as reduced functional ability and low motivation for giving maximum effort in the completion of assigned tasks, a fact that could create problems in collecting reliable data. Consequently, the motivation factor and the way with which it is provided constitute an important parameter for the validity and reliability of results, especially when a study concerns individuals with hearing loss. Researchers (11,13,26
For this sample of subjects with hearing loss, testing was performed on 2 separate days revealing no significant difference in all parameters measured. This finding enhances the confidence that problems such as the lack of motivation or errors that could affect measurements were not present in this study.
Positive findings resulted from the application of the traditional dance program are attributed to a great extent to the exterior motivation provided so much by the percussion instrument (ntaouli) that contributed to the maintenance of music rhythm and by the 2 individuals with typical sense of hearing who provided visual feedback to the dancers with hearing loss. Furthermore, rhythm maintenance and music implementation contributed to a great degree to the achievement of exercise intensity (average around 74% of maximal HR) that is required for the improvement of aerobic capacity (10
Reviewing the literature, a lack of studies is observed regarding the application of training programs and their effect on the physical fitness levels of adults with hearing loss, whereas other relative studies concern mainly children and adolescents (8,15 aerobic capacity and muscle strength of adults with hearing loss.
On the contrary, in relative studies regarding individuals with typical sense of hearing (5,9,10,18,22 10 9 aerobic capacity and increases weight loss rhythm of individuals. Moreover, Flores (9 22 aerobic capacity in 27 women who participated in an aerobic program, reporting that this improvement depends considerably on the intensity of exercise . Also, Millburn and Butts (18 aerobic capacity between dancers and individuals participating in jogging, reported that the 2 activities provided equally good results in terms of improving cardiorespiratory fitness. Finally, in a study concerning ballet dancers (5 2 max improvement was noticed mostly as a result of running activities compared to isometric bar exercises.
An additional parameter measured in this study was isokinetic peak torque of lower extremities for the individuals participating in the program. As a result of the 12-week program, postmeasurements showed that adults with hearing loss improved their muscle strength . Taking into account that the intervention group did not participate previously in any other physical activity or sport for at least 1 year during the program, and the fact that control group individuals who did not participate in the program or other form of exercise did not present any changes in terms of muscle strength of lower extremities, it appears that traditional dances, with the form of a structured and continuous exercise program with alternating intensity, constitute an effective way for improving muscle strength .
As for gender, it is well known that normal values for aerobic power and muscle strength in male untrained or trained individuals are higher compared to the female population. This is in agreement with female and male values, before and after the intervention program, in our study. Moreover, cardiorespiratory and muscle strength adaptations were noted in both genders.
In conclusion, the finding of this study is that adults with hearing loss improved their physical fitness levels, indicating that a traditional dance exercise training program is an effective method to improve aerobic capacity and muscle strength of adults with hearing loss. Improvement of physical abilities enables individuals with hearing loss to become more sociable and capable of integration in the workplace. These findings justify the use of the intervention program described in this study and create new perspectives for more detailed research in the field concerning individuals with hearing loss. Because aerobic capacity and muscle strength are considered the most important components of physical fitness, further effective exercise training programs should be similarly developed for children, adolescents, and young adults with hearing loss.
Practical Applications
Self-isolation phenomenon and marginalization of individuals with hearing loss are facts that contribute to a great degree to the decreased participation in physical activities, resulting in social integration difficulties. Useful conclusions were derived from this present study concerning improvement of physical abilities of adults with hearing loss, particularly through the application of a traditional dance program. The benefits obtained from activity participation with the form of traditional dances probably provide motivation to individuals with hearing loss to form and organize traditional dance groups that will also include individuals with typical sense of hearing, contributing to the social interaction between the 2 populations. Benefits of physical activities combined with possible social and psychological profits derived from the participation in traditional dance programs will constitute an important motivation for the parents of individuals with hearing loss to select traditional dances, as the physical activity aiming to the physical abilities' development of their children, without the fear of failure and disappointment.
Acknowledgments
We are grateful to the group of young adults with hearing loss for their participation in this study. Furthermore, we want to express our gratitude to the traditional dances teachers of adults with hearing loss for their cooperation and unfailing support during traditional dance research. We would also like to thank the entire laboratory and medical staff for their hard work for the completion of this study.
References
1. Althoff, L and Eggert, D. Utersuchungen zur Motorik schwerhorigen Kinder. In
Rehabilitation Behinderten durch Forderung der Motorik . Heesej, G, ed. Berlin: Care Marsh 6ld; Verlagsbuch, 1975.
2. Ammons, DK. Unique identity of the World Games for the Deaf.
Palaestra 5: 40-43, 1990.
3. Bloomquist, LE. Deaf and hard of hearing. In:
Exercise Management for Persons with Chronic Diseases and Disabilities. American College of Sports Medicine (ed.). Champaign, IL: Human Kinetics, 1997. pp. 233-235.
4. Carlson, BR. Assessment of motor ability of selected deaf children in Kansas.
Percept Mot Skills 34: 303-305, 1972.
5. Cohen, JL, Segal, KR, Witriol, I, and Mcardie, W. Cardiorespiratory responses of ballet
exercise and the O
2 max of elite ballet dancers.
Med Sci Sport Exerc 14: 212-217, 1982.
6. diNatal, J, Lee, M, Ward, G, and Shephard, RJ. Loss of physical condition in sightless adolescents during a summer vacation.
APAQ 2: 144-150, 1985.
7. Eggert, D, Ratschinski, G, Rattey, S, and Schillemat, R. Motorischer Entwicklungsstand und motorische Stfirungen bei Schwerhorigen Kinder.
Motorik 9: 4-9, 1986.
8. Ellis, MK. Influences of parents and school on sports participation and fitness levels of deaf children.
Palaestra 77: 44-49, 2001.
9. Flores, R. Improving fitness in African American and Hispanic adolescent.
Pub Health Rep March-April: 189-193, 1995.
10. Garber, CE, McKinney, JS, and Carleton, RA. Is aerobic dance an effective alternative to walk-jog
exercise training?
J Sports Med Phys Fitness 32: 136-141, 1992.
11. Hattin, H, Frasser, M, Ward, GR, and Shephard, RJ. Are deaf child unusually fit? A comparison of fitness between deaf and blind children.
APAQ 3: 268-275, 1986.
12. Health Education Authority.
Young People Physical Activity . HEA, London, 1997.
13. Johnson, O and Gustavson, D. Spirometry and Lung function in children with congenital deafness.
Act Paediatr 94: 723-725, 2005.
14. Kravitz, L and Furst, D. Influence of reward and social support on
exercise adherence in aerobic dance class.
Psyc Reports 69: 423-426, 1991.
15. Lee, M, Ward, G, and Shephard, RJ. Maximizing the working capacity of sightless adolescents.
Dev Med Child Neur 27: 767-774, 1985.
16. Lindsey, D and O'Neal, J. Static and dynamic balance skills of eight-year-old deaf and hearing children.
Am Ann Deaf 121: 49-55, 1976.
17. Mandroukas, K, Angelopoulou, N, Christoulas, K, and Vrabas, I. Cardiorespiratory and metabolic responses during straight and bent knee cycling.
J Sports Med Phys Fitness 40: 145-149, 2000.
18. Millburn, S and Butts, NK. A comparison of the training responses to aerobic dance and jogging in college females.
Med Sci Sports Exerc 15: 510-513, 1983.
19. Pender, RH. A comparison of visual perception and selected motor fitness test items between congenital deaf and hearing children.
Dissertation Abstract 37: 2060, 1976.
20. Shigematsu, R, Chang, M, Yabushita, N, Sakai, T, Nakagaichi, M, Nho, H, and Tanaka, K. Dance-based aerobic
exercise may improve indices of falling risk in older women.
Age Ageing 31: 261-266, 2002.
21. Stewart, DA.
Deaf Sport: The Impact of Sports Within the Deaf Community . Washington. DC: Gallaudet University Press, 1991.
22. Thomsen, D and Ballor, DL. Physiological responses during aerobic dance of individuals grouped by
aerobic capacity and dance experience.
Res Q Exerc Sport 62: 68-72, 1991.
23. USA Deaf Sport Federation. Available at:
http://www.usadsf.org . Accessed November 17, 2006.
24. U.S. Department Of Health and Human Services.
Physical activity and Health: A report of the Surgeon General . Atlanta, GA: U.S Department of Health and Human Services, Centers for Disease Control and Prevention, National Center For Chronic Disease Prevention and Health Promotion, 1996.
25. Wiegersma, PH and Svelde, A. Motor development of deaf children.
J Child Psych Psychiatr 24: 103-111, 1983.
26. Zebrowska, A and Zwierzchowska, A. Spirometric values and aerobic efficiency of children and adolescents with deafness.
J Phys Pharm 57: 443-447, 2006.
27. Zebrowska, A, Zwierzchowska, A, and Gawlic, K. The dynamics of maximal aerobic efficiency in children and adolescents with hearing and visual impairment.
J Human Kinetics 17: 53-63, 2007.
