Marco Antônio Vieira da Silva

OBJECTIVE: The aim of this study was to verify the efficacy of using theory-based strategies on implementation intentions in promoting physical activity (PA) among adults. METHODS: This review was conducted in accordance with the PRISMA recommendations. The search was carried out in seven electronic databases (LILACS, PubMed, SciELO, Cochrane, Web of Science) and two searches of the "grey literature" were performed (Openthesis and OpenGrey). Randomized clinical trials (RCT), published up to September 2016, were considered eligible for this study. Two reviewers independently and systematically evaluated the eligibility criteria, and performed data extraction. A meta-analysis was performed for the purpose of comparing the effect between the intervention and control groups. The effect sizes were grouped in two subgroups with the purpose of more accurately verifying the effect caused by reinforcing the implementation intentions strategy, and using the inverse variance statistical method with random effects models to estimate the main effect of the implementation intention strategy on the PA behavior. Heterogeneity among the studies was evaluated by using I-square statistics, and the Jadad scale to evaluate the quality of included papers. RESULTS: The search resulted in 12,147 records, of which 13 RCTs were considered eligible for this review. Sample age ranged from 18 to 76 years, and participants had conditions such as medullary lesion, coronary disease, obesity, diabetes mellitus, sedentarism or occupational stress. When the summary of the effect was analyzed in the meta-analysis, the result found in the subgroup with reinforcement of the implementation intentions strategy was 0.25 (IC 95% = 0.05-0.45) in favor of the intervention group. This demonstrated that application of the implementation intentions strategy was capable of increasing PA practice in the participants of these studies, in comparison with others that did not use this reinforcement. CONCLUSION: The findings of this review indicated that application of the theory of implementation intentions promoted PA behavior among the adults who received reinforcement of this strategy. The systematic review protocol was registered in the PROSPERO database under the number CRD42018090482.

Type II diabetes mellitus is a highly prevalent disease among the adult Brazilian population, and one that can be controlled by interventions such as physical activity, among others. The aim of this randomized controlled study was to evaluate the impact of a traditional motivational strategy, associated with the activation of intention theory, on adherence to physical activity in patients with type II, diabetes mellitus who are part of the Unified Health System (SUS). Participants were divided into a control group (CG) and an intervention group (IG). In both groups, the traditional motivational strategy was applied, but the activation of intention strategy was only applied to the IG Group. After a two-month follow-up, statistically significant differences were verified between the groups, related to the practice of walking (p = 0.0050), number of days per week (p = 0.0076), minutes per day (p = 0.0050) and minutes walking per week (p = 0.0015). At the end of the intervention, statistically significant differences in abdominal circumference (p = 0.0048) between the groups were observed. The conclusion drawn is that the activation of intention strategy had greater impact on adherence to physical activity and reduction in abdominal circumference in type II diabetics, than traditional motivational strategy.

OBJECTIVE: To evaluate the effect of implementation intentions as an intervention strategy to promote walking in adults with type 2 diabetes mellitus (T2DM). METHODS: We conducted a controlled and randomized trial, with 12 months of follow-up, involving 65 people with T2DM recruited from primary health care units and allocated them in the control group (CG, n = 32) and intervention group (IG, n = 33). The IG received the implementation intention strategy to promote walking and the CG remained in follow-up for conventional treatment in primary health care. The researchers were blinded by anthropometric measurements and the filling of the instruments. RESULTS: After twelve months of follow up, the IG presented a statistically significant increase in the leisure time physical activity when compared with the CG (p = 0.0413) and showed a significant decrease in waist circumference (p = 0.0061). No significant difference was observed regarding body mass index and glycated hemoglobin among groups. CONCLUSIONS: Implementation intention was effective in promoting walking and improving clinical indicators in adults with T2DM.

Background The practice of daily aerobic exercise such as healthy walking could have an important effect on cardiovascular parameters. However, there is still little evidence of how much weekly walking volume is enough to influence cardiovascular autonomic modulation and arterial stiffness on hypertension. Purpose To assess effects of weekly walking volume on cardiac autonomic function and arterial stiffness index in elderly hypertensive. Methods Sixty hypertensive elderly with 71.7 ± 3.4 years old were allocated in physically inactive (PI, n=30) and active (PA, n=30) groups. Hemodynamic parameters of heart rate (HR), peripheral blood pressure (SYS, DIA, MBP), cardiac autonomic modulation by the method of HR variability in both the time (root mean square of successive differences (RMSSD) and percentage of RR intervals differing by <50ms (pNN50)) and frequency domains (low and high frequency (LF, HF), and LF/HF ratio), stiffness (augmentation index; AIX, pulse wave velocity; PWV) and total vascular conductance (TVC), and central blood pressure (cSYS, cDIA) were measured in baseline conditions. Results The average of weekly walk in PA group was 312.4 ± 36.5 min. vs. 57.7 ± 47.9 min. in PI group (p <0.001). Pronounced resting bradycardia was observed in PA group (62.1 ± 8.7 bpm) in comparison with PI group (75.7 ± 9.1; p=0.0). Brachial SYS (124.3 ± 7.6 mmHg) DIA (76.5 ± 7.4 mmHg) and MBP (92.4 ± 7.4 mmHg) were lowers in PA than PI group (133.6 ± 6.0 mmHg; p=0.003), (82.7 ± 7.6 mmHg; p=0.032) and (99.4 ± 7.0 mmHg; p<0.05), respectively. The PA group showed higher cardiac parasympathetic modulation than PI group, evidenced by an increase in RMSSD (PI: 43.8 ± 23.9 vs. PA: 69.4 ± 29.4 ms; p=0.047), pNN50 (22.7 ± 3.9 vs. 40.7 ± 5.1 %; p=0.038) and in cardiac HF band (PI: 59.9 ± 5.8 vs. PA: 67.0 ± 3.7 nu; p=0.005). There were no differences in sympathetic modulation between PA and PI groups. The PI group had higher PWV (10.3 ± 1.2 m/s), AIX (36.4 ± 8.0 %) and TVC (1.4 ± 0.1 s*mmHg/ml) when compared to PA group (PWV = 9.1 ± 0.7 m/s; p = 0.005), (AIX = 23.5 ± 13.6 %; p = 0.003) and (TVC = 1.2 ± 0.1 s*mmHg/ml; p <0.001). Additionally, the cSYS (119.5 ± 14.0 mmHg) and cDIA (76.2 ± 18.3 mmHg) were lower in PA than PI (135.8 ± 20.6 mmHg; p=0.045 and 91.8 ± 20.5 mmHg; p=0.034), respectively. Conclusion These findings suggest that a higher weekly volume of walking improves baseline hemodynamic parameters and provides greater vagal modulation at rest, concomitant with attenuation of arterial stiffness evidencing that this type of intervention has important cardiovascular safety. Support or Funding Information CAPES, CNPq, FAPEMIG, UFTM.