100
Journal of Exercise Physiologyonline June 2017 Volume 20 Number 3
Editor-in-Chief Official Research Journal of the American Society of Tommy Boone, PhD, MBA Review Board Exercise Physiologists Todd Astorino, PhD ISSN 1097-9751 Julien Baker, PhD Steve Brock, PhD Lance Dalleck, PhD Eric Goulet, PhD Robert Gotshall, PhD Alexander Hutchison, PhD M. Knight-Maloney, PhD Len Kravitz, PhD James Laskin, PhD Yit Aun Lim, PhD Lonnie Lowery, PhD Derek Marks, PhD Cristine Mermier, PhD Robert Robergs, PhD Chantal Vella, PhD Dale Wagner, PhD Frank Wyatt, PhD Ben Zhou, PhD
Official Research Journal of the American Society of Exercise Physiologists
ISSN 1097-9751
JEPonline Physical Exercise Program Carried Out in Primary Health Care Units Improves Exercise Tolerance and Economy of Movement Camila B. Papini1, Priscila M. Nakamura2, Grace Angélica de Oliveria Gomes3, Danilo R. Bertucci4, Eduardo Kokubun5 1
Science Sport Departament, Federal University of Triangulo Mineiro, Uberaba / MG, Brazil, 2Federal Institute of Education, Science and Techonology of South of Minas Gerais, Muzambinho / MG, Brazil, 3Departament of Gerontology, Federal University of São Carlos, São Carlos / SP, Brazil, 4Postgraduated Program in in Motor Science, UNESP, Rio Claro / SP, Brazil, 5Department of Physical Education, Sao Paulo State University, Rio Claro / SP, Brazil ABSTRACT Papini CB, Nakamura PM, Gomes GAO, Bertucci DR, Kokubun E. Physical Exercise Program Carried Out in Primary Health Care Units Improves Exercise Tolerance and Economy of Movement. JEPonline 2017;20(3):100-109. The purpose of this study was to evaluate the effect of a 1 yr exercise program carried out in Primary Health Care Units (PHCU) concerning the variables related to cardiorespiratory fitness (CF). A quasi-experimental study was performed with 22 women (56.35 ± 9.25 yrs old). The intervention was comprised of 3, 90-min sessions·wk-1. The subjects’ CF was measured via submaximal incremental treadmill test through indirect calorimetry. A significant difference in the subjects’ final exercise time (in minutes) was found between the initial test and the 1 yr test [Baseline (BL) = 6.36 ± 3.2 and at 1 yr (1Y) = 10.80 ± 5.0 min; P = 0.004] and final exercise stage (BL = 2.2 ± 1.2 and 1Y = 3.6 ± 1.7, P = 0.004). The number of completed minutes and stages during the treadmill test was significantly increased after the 1 yr physical exercise program carried out in the PHCU. Thus, the subjects’ exercise tolerance and economy of movement were improved. Key Words: Economy of Movement, Exercise Intervention, Exercise Tolerance, Primary Health Care Units
101
INTRODUCTION Maintaining or improving the cardiorespiratory fitness of adults is important throughout life, regardless of age. Cardiorespiratory fitness is inversely related to mortality by coronary disease, cerebral vascular accident, and all mortality causes (17). In addition, it is increasingly clear that poor cardiorespiratory fitness is an important predictor for metabolic syndrome (18). Hence, the potential benefit of increased cardiorespiratory fitness should be considered for primary prevention of numerous chronic diseases such as obesity, hypertension, and type 2 diabetes mellitus. Despite the fact that cardiorespiratory fitness is linked to a genetic component as well as to gender, age, and clinical conditions of the cardiovascular system, it can be influenced by external factors (especially physical activity and fitness training levels) (4,8). Structured physical exercise interventions result in beneficial changes in the structure and function of the heart and lungs (7). Perhaps, the most obvious physiological adaptation is the increase in maximal oxygen uptake and exercise tolerance, the improvement in submaximal exercise intensities, the decrease in expired ventilation, heart rate, and blood pressure at rest and during exercise (1). Considering both the relationship between cardiorespiratory fitness and health and the high prevalence of physical inactivity (26), it is necessary to elaborate, implement, and evaluate physical exercise programs that focus on adults, elderly, and children. Primary Health Care Centers are a convenient setting to carry out exercise programs since they are responsible for promoting the client and/or patient’s health and quality of life (11). In Brazil, in particular, ~40% of the Primary Health Care Centers have physical activity interventions (11). Programs carried out in the SUS (Public Health Brazilian System, Sistema Único de Saúde, in Portuguese) can reach individuals with low socioeconomic and schooling level since the Health Units are mostly located in areas of high vulnerability in Brazil. Then, given the studies by Codogno et al. (6) and Turi et al. (25) that show the increase in the level of physical activity and the practice of walking are effective in the mitigation of health care expenditures in the Brazilians users of SUS. Presently, however, the development of physical exercises programs in Primary Health Care is limited by the lack of materials, inappropriate places to perform physical exercises, and the difficulty in monitoring the intensity of exercise. Despite these difficulties, numerous physical exercises programs carried out in the Brazilian Public Health System have resulted in large health benefits related to cardiorespiratory fitness (20,21,23). The purpose of this study was to evaluate the effect of 1 year of physical exercise program carried out in Primary Health Care Units on exercise tolerance and economy of movement through an indirect calorimetric method in women. METHODS Subjects This 1 year quasi-experimental study was developed in two Primary Health Care Units in Rio Claro City, Brazil. Adult females were recruited by flyers and newspaper advertisements. The participants were assigned to the intervention group based upon proximity from their residence, considering the “territorialization principle” of SUS.
102
Forty-nine subjects were recruited at the beginning of intervention. As a result of either voluntary dropout or failure to meet the inclusion criterion for the study with a frequency of 75% attendance in the sessions, 22 subjects (56.35 ± 9.25 yrs old) remained in the intervention after 1 year (Figure 1). The study was approved by the Human Research Ethics Committee of Biosciences Institute, UNESP, protocol number 2308.
Figure 1. Flow Chart of Subjects and Dropouts. Physical Exercise Intervention The community based exercise intervention used in this study was comprised of 3, 90-min sessions·wk-1 of physical exercises. The intervention was designed to meet current recommendations for physical activity (2,22) and all sessions were guided by a physical education professional. The sessions were divided into warm-up activities (10 min), moderate intensity aerobic exercise (50 min), strength-training exercises (20 min), and cool-down activities (10 min). Thus, the participants performed 150 min of aerobic exercises, 60 min of strength exercises, and 30 min of stretching exercises weekly. The warm-up and cool-down activities included static stretching exercises and articular movements. Static stretching was maintained for a minimum period of 15 to 30 sec, twice for each muscle group. The subjects were advised to sustain a muscle stretch that did not cause pain. The strength-training exercises were performed using free weights, exercise mats, and latex exercise bands. Exercises included all major muscle groups, and were performed in 3 sets of 30 sec followed by 1 min of recovery. The aerobic exercises consisted of walking at moderate intensity (60 to 70% of peak heart rate). The target zone for exercise was calculated using the equation HR peak = 206 − (0.88 × age) (13). All subjects were encouraged to maintain a subjective effort of a rating of perceived exertion between 13 and 15 on the 20-point Borg color scale (5,24) during walking. Four subjects were randomly selected to measure the intensity of their activity twice a month using a cardiac rate monitor (Polar® model FS1, Polar Electro Oy, Finland) and the subjective effort scale. The cardiac rate and the Borg scale were monitored each 10 min of the session.
103
Cardiorespiratory Fitness Test The subjects’ cardiorespiratory fitness was measured via submaximal incremental treadmill test (ATL3®, Inbrasport, Brasil) through indirect calorimetry using a gas analyzer (VO2000, Medgraphics, St. Paul, Minnesota, USA) and a medium flow pneumotachograph (6 to 120 L·min-1). The ergoespirometric test data were collected in each of 3 breaths by Aerograph Software. The subjects answered the Readiness Activity PAR-Q questionnaire before the test and performed an adaptation on the treadmill using the neoprene masks. They performed the test at baseline (BL) and after 1 yr (1Y) of intervention. The test was initiated at 4 km·h-1 with no incline. In the second stage, the speed was increased to 5.6 km·h-1 with no incline. In the next stages, the speed was maintained and the incline was increased by 2.5% in each 3-min stage. The subjects’ Maximum Heart Rate (HRmax) was calculated according to the equation: HRmax = 220 – age (16). Heart rate was monitored during the test (using a Polar® model FS1, Polar Electro Oy, Finland). The scale BORG was also used during every minute of the test to monitor the subjective effort perception (5). The test was interrupted when the subject reached 85% of HRmax, which was either previously estimated by the equation (HR85% = (HRmax x 85)/100) or when the subject reached the BORG 15 (in case of the subject’s medicated with beta-blockers) or by voluntary exhaustion (before reaching 85% of HRmax). The final BORG and HR reached in the test were used to verify if the test interruption was the same in pre- and post-evaluation. The variables used to verify the changes in cardiorespiratory fitness were: (a) final time and stage (exercise tolerance) reached in the tests; and (b) energy cost (economy of movement) for each stage. The subject’s energy cost was calculated via Delta (absolute difference of VO2 (mL·kg-1·min-1) between pre- and post-tests, using the equation: D = VO2 pre – VO2 post. The corresponding difference was calculated in percentage (%) after. Statistical Analysis The data normality was verified through Shapiro-Wilk test. Descriptive data were reported as means and standard deviations. The paired Student´s t-Test was used to compare the changes in final VO2 and final HR. The paired Wilcoxon test was used to compare the final BORG, stage and time reached in the tests. Statistical analyses were conducted using SPSS 17.0, with the alpha level set at P0.05) between BL and 1Y for final HR, VO2, and BORG as presented in Table 1. Significant differences were indicated between tests for final time and final stage reached in the ergoespirometric test.
104
Table 1. Comparison Between Ergoespirometric Variables Related to Exercise Tolerance at Baseline and After 1 Yr of intervention. Baseline
1 yr
P value
HRfinal (beats·min-1)
140.4 ± 14.88
140.6 ± 15.89
0.869
VO2final (mL·kg-1·min-1)
19.28 ± 3 .37
19.30 ± 3.45
0.972
BORGfinal
14.5 ± 2.17
15.35 ± 1.38
0.115
Final Time (min)
6.36 ± 3.45
10.80 ± 5.00
0.004*
2.2 ± 1.2
3.6 ± 1.7
0.004*
Final Stage
HRfinal = Final Heart Rate; VO2final = Final Oxygen Uptake; BORGfinal = Subjective Effort Scale Reached at the End of Test
The Table 2 shows the Delta value (absolute changes) and the percentage changes (%) for energy cost, and the number of subjects that completed each stage in baseline and after 1 yr of intervention. Few subjects could complete more than 3 or 4 stages at baseline. However, most subjects completed the 3 stages and some of them completed from 4 to 7 stages after 1 yr of intervention. Table 2 points out that the negative Delta in each stage indicates a decrease in VO2 after 1 yr of intervention. The decrease in Delta value ranged around 12% to 21%. Table 2. Energy Cost (VO2 – mL·kg-1·min-1), Delta (Absolute Changes) and Percentage Changes (%) for Each Stage at Baseline and After 1 Yr of Intervention. Stages
Baseline
n
1 Yr
n
Delta
%
1
14.56 ± 2.77
22
11.63 ± 3.10
22
-2.93
20.1
2
18.41 ± 3.13
17
16.03 ± 3.62
21
-2.38
12.9
3
20.61 ± 2.23
9
16.83 ± 3.73
14
-3.78
18.3
4
22.01 ± 2.16
4
17.69 ± 3.83
10
-4.32
19.6
5
22.99 ± 3.24
2
17.55 ± 2.51
8
-5.44
23.66
6
20.37
1
21.27 ± 1.98
3
-
-
7
-
0
22.91
1
-
-
-The Stages 6 and 7 were not compared due the small number of subjects.
105
DISCUSSION The results indicate that the intervention carried out in Primary Health Care was effective in improving the variables related to cardiorespiratory fitness. The significant difference for final time and stage between the tests indicates that the subjects developed a greater exercise tolerance. Moreover, the increase in the subjects’ exercise tolerance was confirmed by the low energetic cost presented in each stage at baseline and after 1 yr of intervention. It was also observed that at baseline, few subjects completed more than 3 or 4 stages, while most of the subjects completed the 3 stages and others completed from 4 to 7 stages after 1 yr. These results indicate an improvement in walking capacity and greater endurance. The intervention offered in this study incorporated the physical activity recommendation of 150 min of moderate aerobic exercise combined with 60 min of resistance muscle exercises weekly (2,22). This exercise prescription is adequate to promote physiological adaptations that result in an improvement of cardiovascular and respiratory functions and, consequently, an increase in exercise tolerance along with a low energetic cost during the walking movement. Similar results were also found by other studies. Belli et al. (3) evaluated 9 sedentary subjects (53.4 ± 2.3 yrs old) that performed 12 months of intervention, which consisted of walking 3 times·wk-1 from 20 to 60 min. The results corroborate our study once an increase of the final speed and final time reached in the incremental test was observed. Additionally, the VO2peak had a significant increase after 12 months of intervention. Although VO2 max was not evaluated in our study, the increase in final time and stage between tests suggest a possible increase. Nakamura et al. (21) evaluated the effect of a 10-yr physical exercise program carried out in a Primary Health Care setting. The subjects included 409 females (50.0 ± 26 yrs old) and 64 males (64.0 ± 10 yrs old). The authors concluded that the subjects’ cardiorespiratory fitness was improved once the subjects significantly decreased the time to perform the walking test over the 10-yr period. Being functionality independent is an important goal among older adults. However, some physiological alterations that occur with the natural process of aging can make it difficult to achieve. Additionally, the aging process among elderly individuals decreases the total energy available to perform the daily physical activities (27). Therefore, it is evident of the importance in improving or maintaining the cardiorespiratory fitness levels throughout the course of life. While cardiorespiratory fitness usually presents a progressive increase with the course of chronological age, starting with the third decade of life in untrained individuals both the cardiovascular and respiratory systems suffer a decrease with age of ~10% every decade (10). According to Hagberg (14), elderly individuals who maintain their physical activity level can minimize the natural cardiorespiratory fitness decline at a rate of 5% per decade, which is half the decline in relation to sedentary people. Thus, the increase or maintenance of physical activity levels such as the participation in a physical exercise program is important to healthy aging.
106
The similar values for the final VO2, HR, and BORG in baseline and after 1 yr indicate that both tests were performed until the same criteria interruption (85% of HRmax and BORG 15). One of the study limitations was not to perform the maximum effort test until the subjects’ voluntary exhaustion to verify the improvement in cardiorespiratory fitness. The submaximal effort test had to be performed once the guidelines recommended that the maximum effort test should not be performed when some risk factors were presented by the subjects (such as hypertension, diabetes, advanced age, and when there was not a doctor present) (1,9,12,15,19). Although direct determination of VO2 max is the most accurate method to measure cardiorespiratory fitness, it requires a maximal level of exertion that increases the risk of adverse events in individuals with an intermediate to high risk of cardiovascular problems. Walk tests are accessible to anybody without locomotion impairments, and they are useful when running is not advisable, such as in obese or elderly individuals. Thus, the test protocol choice with the incremental incline was made in reference to the physical conditions of the subjects. Some of the subjects did not have sufficient mobility to walk very quickly and/or run on the treadmill. Some studies (20,23) that assessed the VO2 max of participants have demonstrated that physical exercise programs carried out in the Primary Health Care setting are effective in improving cardiorespiratory fitness in mature adults and in elderly individuals. Petrella et al. (23) evaluated 131 healthy subjects (>65 yrs old) in a Primary Health Care setting that involved counseling and exercise prescription for a period of 1 yr. The results indicated that was a significant increase of 11% in VO2 max after 6 months and a 12% increase after 1 yr. Monteiro et al. (20) investigated the effect of a physical exercise program carried out in a Primary Health Care setting that involved 16 participants (56 ± 3 yrs old) over a 4-month period. The program resulted in a 42% improvement in VO2 max. Although the VO2 max of subjects in the present study was not assessed, the findings do indicate that there was a decrease in the subjects’ energy cost and an increase in exercise tolerance. Being able to walk at 5.6 km·h-1 with some incline is an improvement that is consistent with a better quality of life. Elderly people do not need to reach advanced stages in the treadmill test considering the amount of effort needed to perform their daily activities. It should be pointed out that the small number of subjects after 1 yr of intervention was due to the difficulty to maintain 75% of attendance in the sessions. Although the subjects who did not meet 75% of attendance were excluded from statistical analysis, they were not excluded from the program. This decision on behalf of the participants was considered important since there was no physical exercise program offered in other locations, especially since the participants were allocated a Health Unit near their residence (which is consistent with the “territorialization principle” of SUS). Considering the relation between cardiorespiratory fitness and improvement in health and the benefits that regular aerobic exercise promotes in participants, it is imperative (especially with regard to the participants’ physiological and functional concerns) that such community-based exercise programs are designed, implemented, and evaluated. The development of physical exercise programs in Primary Health Care in Health Units throughout Brazil is a good
107
strategy to improve cardiorespiratory fitness of the users of the lower income populations in terms of low socioeconomic status and schooling. CONCLUSIONS The physical exercise program carried out in Health Units was effective in promoting an improvement in variables related to cardiorespiratory fitness. The significant increase of final time and stage indicates that the participants developed a greater exercise tolerance. Moreover, the decrease obtained in energy cost reflects an economy of movement during walking. The participants were able to expend less physical effort for the same intensity of exercise. These improvements should have a positive impact on the daily physical activities and quality of life of the participants.
ACKNOWLEDGMENTS The authors thank CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, in Portuguese), Brazil. Address for correspondence: Camila B. Papini, PhD, Science Sport Departament, Federal University of Triangulo Mineiro - Av. Getúlio Guarita, 159, Nossa Senhora da Abadia, Uberaba City, Minas Gerais, zip-code 38.025-440, Email:
[email protected] REFERENCES 1. American College of Sports Medicine. ACSM's Guidelines for Exercise Testing and Prescription. Philidelphia, PA: Lippincott Williams & Wilkins, 2013. 2. American College of Sports Medicine. ACSM Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: Guidance for prescribing exercise. Med Sci Sports Exer. 2011;43(7):1334-1359. 3. Belli T, Ribeiro LFP, Ackermann MA, Baldissera V, Gobatto CA, da Silva RG. Effects of 12-week overground walking training at ventilatory threshold velocity in type 2 diabetic women. Diabetes Res Clin Prac. 2011;93(3):337-343. 4. Blair S, Cheng Y, Holder J. Is physical activity or physical fitness more important in defining health benefits? Med Sci Sports Exer. 2001;33:S379-S99. 5. Borg G. Psychophysical bases of perceived exertion. Med Sci Sports Exerc. 1982;14 (5):377-381. 6. Codogno JS, Turi BC, Kemper HC, Fernandes RA, Christofaro DGD, Monteiro HL. Physical inactivity of adults and 1-year health care expenditures in Brazil. Inter J Publ Health. 2015;60(3):309-316.
108
7. Dunn A, Marcus B, Kampert J. Comparison of lifestyle and structured interventions to increase physical activity and cardiorespiratory fitness: A randomized trial. JAMA. 1999;281(4):327-334. 8. Fletcher G, Balady G, Froelicher V. Exercise standards a statement for healthcare professionals from the American Heart Association. Circ. 1995;(82):2286-2322. 9. Ghorayeb N, Costa R, Castro I. Diretriz em cardiologia do esporte e do exercício da Sociedade Brasileira de Cardiologia e da Sociedade Brasileira de Medicina do Esporte. Arquivos Brasileiros de Cardiologia. 2013;100(1):1-41. 10. Gobbi S, Villar R, Zago AS. Bases teóricos-práticas do condicionamento físico. (1st Edition), Rio de Janeiro, RJ: Guanabara Koogan, 2005. 11. Gomes GAO, Kokubun E, Mielke GI, Ramos LR, Pratt M et al. Characteristics of physical activity programs in the Brazilian primary health care system. Cad Saúde Pública. 2014;30(10):2155-2168. 12. Guimarães J, Stein R, Vilas-Boas F. Normatização de técnicas e equipamentos para realização de exames em ergometria e ergoespirometria, Arquivos Brasileiros de Cardiologia. 2003;80:457-464. 13. Gulati M, Shaw LJ, Thisted RA, Black HR, Merz CNB, Arnsdorf MF. Heart rate response to exercise stress testing in asymptomatic women the St. James women take heart project. Circ. 2010;122:130-137. 14. Hagberg J. Effect of training on the decline of VO2max with aging, Fed Proceed. 1987;46(5):1830-1833. 15. Harris G, White R. Exercise stress testing in patients with type 2 diabetes: When are asymptomatic patients screened? Clin Diab. 2007;25(4):126-130. 16. Karvonen M, Kentala E, Mustala O. The effects of training on heart rate: a longitudinal study. Annales medicinae experimentalis et biologiae Fenniae. 1957;35(3):307. 17. Kodama S, Saito K, Tanaka S, Maki M, Yachi Y, et al. Cardiorespiratiry fitness as a quantitative predictor of all-cause mortality and cardiovascular events in healthy men and women. JAMA. 2009;301(19):2024-2035. 18. Lamonte M, Barlow C, Jurca R. Cardiorespiratory fitness is inversely associated with the incidence of metabolic syndrome a prospective study of men and women. Circ. 2005;112(2):505-512. 19. Meneghelo R, Araújo C. III Diretrizes da Sociedade Brasileira de Cardiologia sobre teste ergométrico. Arquivos Brasileiros de Cardiologia. 2010;95(5):1-26.
109
20. Monteiro H, Rolim L. Efetividade de um programa de exercícios no condicionamento físico, perfil metabólico e pressão arterial de pacientes hipertensos. Rev Bras Med Esporte. 2007;13(2):107-112. 21. Nakamura PM, Papini CB, Teixeira IP, Chiyoda A, Luciano E, Cordeira KL, Kokubun E. Effect on physical fitness of a 10-year physical activity intervention in primary health care settings. J Phys Act Health. 2015;12(1):102-108. 22. Pate RR, Pratt M, Blair SN, Haskell WL, Macera CA, Bouchard C, Kriska A. Physical activity and public health: a recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine. JAMA. 1995;273(5):402407. 23. Petrella R, Koval J. Can primary care doctors prescribe exercise to improve fitness? The step test exercise prescription (STEP) project, Am J Prevent Med. 2003;24(4): 316–322. 24. Serafim THS, Nakamura PM, Pereira G, Nakamura FY, Kokubun E. Development of the color scale of perceived exertion: Preliminary validation, Percept Motor Skills. 2014;118:884-900. 25. Turi BC, Codogno, JS, Fernandes RA, Monteiro HL. Caminhada e gastos com saúde em adultos usuários do sistema público de saúde brasileiro: estudo transversal retrospectivo. Ciência & Saúde Coletiva. 2015;20(11):3561-3568. 26. Vigitel Brasil. Vigilância de Fatores de Risco e Proteção para Doenças Crônicas por Inquérito Telefônico: 2014. Ministério da Saúde, Secretaria de Vigilância em Saúde, Departamento de Vigilância de Doenças e Agravos não Transmissíveis e Promoção da Saúde, – Brasília: Ministério da Saúde, 2015. 27. Wert D, Brach J. The association between energy cost of walking and physical function in older adults. Arch Gerontol Geriatr. 2013;57(2):198-203. Disclaimer The opinions expressed in JEPonline are those of the authors and are not attributable to JEPonline, the editorial staff or the ASEP organization.