Something you have done easily for years has become harder.
Maybe you tire sooner. You need more time to recover after a long day. Staying up late affects you more than it once did. Or perhaps the change goes in the other direction. Something that overwhelmed you when you were younger no longer seems particularly difficult.
It can be tempting to ask what happened. Sometimes something did. But sometimes part of what happened is that you are no longer the same age.
We do not function apart from where we are in the course of a life. A twelve-year-old, a thirty-year-old, and an eighty-year-old are not simply the same person with different numbers attached to them. Their bodies are different. What is expected of them is different. What they have experienced is different. What they need and what they can readily do may be different.
Some changes are strongly connected to physical development. Puberty changes the body dramatically. Pregnancy and childbirth can alter physical condition and daily life. Age-related hormonal changes, including menopause and andropause, can affect how someone feels and functions. Strength, sensory function, sleep, sexual functioning, mobility, and recovery can also change with age.
But life stage is not only biological.
Leaving home, raising children, caring for aging parents, losing a partner, retiring from work, or becoming responsible for things someone never had to manage before can change the conditions of everyday life. Some stages bring more independence. Others bring greater responsibility or dependence on other people.
The same difficulty can therefore mean something different at different ages. A teenager who needs help managing ordinary responsibilities is in a different situation from a forty-year-old who suddenly begins struggling with things they previously managed easily. An older person who needs more recovery after physical exertion is not necessarily showing the same problem as a younger person who becomes exhausted by minimal activity.
Age does not explain everything, and it should not become an easy explanation whenever something changes. People of the same age differ enormously. Some capacities increase while others diminish. Health, constitution, activity, environment, resources, and experience all affect what someone can do.
Nor does getting older simply mean becoming less capable. Experience can make some situations easier. Skills become practiced. Judgment can improve. A person may understand their own needs better and organize life around them more effectively. Things that once consumed enormous emotional energy may eventually require much less.
The point is not to decide what someone should be able to do at a particular age.
It is to remember that age and life stage are part of the conditions in which a person is functioning. When something changes, we can ask about illness, stress, relationships, patterns, sleep, nourishment, environment, and all the other conditions that may be contributing.
Sometimes we also need to ask a simpler question.
Where is this person in their life?