curl --request GET \
  --url https://app-api.spikeapi.com/v3/userproperties \
  --header 'Authorization: Bearer <token>'

{
  "properties": {
    "birth_date": "<string>",
    "birth_year": 123,
    "body_bone_mass": 123,
    "body_fat": 123,
    "body_mass_index": 123,
    "height": 123,
    "language": "<string>",
    "resting_heartrate": 123,
    "timezone": "<string>",
    "weight": 123
  }
}