Cardiac Rehabilitation Programs (CRP) following an acute coronary syndrome have shown to be effective in reducing mortality. The aim of our study is to investigate the seasonal influence on adherence to physical activity after one year of CRP.

We prospectively collected data from all the patients that underwent CRP during one year and divided them in two groups: patients who finished phase II in cold months (October to March), and those who ended in hot months (April to September).

They completed an exercise-based CRP during 6–12 weeks and were evaluated by a stress test in 3 different moments: ST1 (before the CRP); ST2 (after phase II of CRP) and ST3 (12 months after ST1). We performed a two-sample t-test (pvalue 0.05) between the results obtained in stress test (measured through METs achieved) in the two groups in the 3 moments.

During 2016, 102 patients, aged<65 enrolled phase II after an acute coronary syndrome. There were 21 missing cases.

We found no statistically difference between the results of two groups, after one year.

However, all patients (n=81) presented a positive evolution between ST1 and ST2 and also between ST1 and ST3, in this case with a statistically significance (two-sample t-test (P-value 0.05)) corroborating the result.

On the other hand, the overall outcome between ST2 and ST3 was negative or null.

Although we found no difference in our sample, it's still relevant to analyze the seasonal influence in a larger population.

The results also show the importance of the CRP after an acute coronary syndrome and demonstrate the need to implement a phase III or other forms of incentive physical activity after hospital discharge from phase II.