Answer:
That is an excellent question. A study in the AHA journal Circulation addressed this question. The title says it all: "Physical Fitness Trumps Body Weight in Reducing Death Risks".
The study looked at 14,345 adult men and found:
This is good news for people who have trouble losing weight but are still physically active. For example, in a very simplistic way comparing two equally moderately overweight people, the person who maintained their level of fitness would have a lower chance of a cardiac event than the one who lost weight but was inactive. Physical activity is defined as 30 minutes of vigorous exercise daily.
Of course, accomplishing both goals is the ideal: Maintaining a healthy BMI and staying physically fit through exercise.
The study looked at 14,345 adult men and found:
- Maintaining or improving fitness was associated with a lower death risk, even after controlling for Body Mass Index (BMI) change.
- Every unit of increased fitness (measured as MET, metabolic equivalent of task) over six years was associated with a 19 percent lower risk of heart disease and stroke-related deaths and a 15 percent lower risk of death from any cause.
- Becoming less fit was linked to higher death risk, regardless of BMI changes.
- BMI change was not associated with death risks.
This is good news for people who have trouble losing weight but are still physically active. For example, in a very simplistic way comparing two equally moderately overweight people, the person who maintained their level of fitness would have a lower chance of a cardiac event than the one who lost weight but was inactive. Physical activity is defined as 30 minutes of vigorous exercise daily.
Of course, accomplishing both goals is the ideal: Maintaining a healthy BMI and staying physically fit through exercise.