Var1 is heart rate. Var 2 is systolic blood pressure.

As you may be able to tell, this scatter plot is certainly "scattered." There is a weak correlation between the two values. There is a slightly negative correlation between the two values with the correlation coefficient at -0.1139. Correlation squared is 0.013. This means that very, very few variations lie on the straight-line relationship. There are many outliers.

I think that exercise and increased heart rate may affect the blood pressure of a person with cardiovascular disease more than a young and healthy person. The data also may be confounded by the amount of exertion during the run, caffeine intake, time it took to complete the mile and length of rest time before checking the blood pressure.

Back to my initial proposal