Summarise the Psychological Benefits of Regular Play for Adults

You feel vaguely guilty every time you do something purely for fun, or you live with someone who thinks hobbies are for children. This pulls together what the research actually says: what counts as play, what it does for your head, and what skipping it quietly costs you.

<context>
You want to make a clear case to yourself or someone else for why adults who take play seriously are not being childish but are actively investing in their mental health and performance.
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<task>
1. Define what counts as play for an adult (hint: it is about intrinsic motivation and low stakes, not the activity itself)
2. Name three specific psychological benefits of regular play that have research support
3. Explain why adults tend to deprioritise play and what the cumulative cost of this is
4. Give one example of a play activity that also builds a transferable skill
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<output_format>
- Four numbered sections, two to four sentences each
- Anchor claims to research where possible
- Length: 200 to 300 words
- Tone: confident and direct
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