Maybe your routine hasn't changed very much, but your body has started responding differently. A late night seems to cost more the next day. Sleep feels lighter. Your usual workout takes longer to recover from. Your shape changes even though the number on the scale hasn't moved much. Hunger arrives at unfamiliar times. Stress seems to linger. And eventually a question appears: Why does my body feel so different after 40? The reassuring part is that noticing a difference does