Confirming the value of building a strong exercise habit as a young adult. Don’t worry about what you do…just do…and keep doing. Add variety and intensity when you feel ready. Your body will tell you when you are either not doing enough or too much. The data here are especially important for parents..encourage your daughters to become as fit as possible early in life and to embrace the value of fitness for not just physical health but emotional and intellectual health as well. And, just so we are clear, fit is not the same as skinny. Fit is fit. Skinny is, well, I am not sure what it is but I know that it is not the same thing as fit. Go for fit. It matters. I promise you it does.

Results. In women with a healthy BMI in 2000, there were clear dose-response relationships between accumulated PA and transition to overweight (P=.03) and obesity (P<.01) between 2000 and 2012. The critical periods analysis indicated that very active levels of PA at the 2006 survey (when the women were 28-33 years old) and active or very active PA at the 2009 survey (age 31-36 years) were most protective against transitioning to overweight and obesity.

Conclusion.These findings confirm that maintenance of very high PA levels throughout young adulthood will significantly reduce the risk of becoming overweight or obese. There seems to be a critical period for maintaining high levels of activity at the life stage when many women face competing demands of caring for infants and young children.

Source: Long-term Effects of Physical Activity Level on Changes in Healthy Body Mass Index Over 12 Years in Young Adult Women – Mayo Clinic Proceedings