A co-worker of mine goes out every day for a walk/run up and down the roads and hills surrounding our office building - rain or shine, summer or winter. When asked why she goes out running in single digit temperatures, she exclaims, “Because it makes me feel good!”

Everyone knows the mood-elevating benefits of a good workout. When we don’t get exercise, or think we are not getting enough, it can affect how we feel emotionally, but can it affect us physically?

A new study by Harvard University psychologist Ellen Langer and her student Alia Crum indicates that mind-set can inhibit or enhance the health benefits of exercise. In other words, what you do physically in your daily routine will be more beneficial to you health-wise if you are aware of the exercise you are getting.

Researchers studied 84 female hotel housekeepers. Women in 4 hotels were told that the exercise they got while cleaning rooms was sufficient to meet the requirements for a healthy and active lifestyle. Women in 3 other hotels were told nothing.

Four weeks later, the researchers assessed the women’s health. On average, the women who were informed that their work was healthy exercise had lost 2 pounds, lowered their blood pressure and improved their BMI (body mass index). The changes were significantly higher than in the group of women who were told nothing.

Researchers call this the “placebo effect”. The research shows that our mind-set plays a role in our health and that many of the beneficial results of exercise are due to the placebo effect; we reap more benefits from exercise if we expect to.