[Cryptography] athletic event verification?

[Henry Baker]

[I'm asking this question for academic interest only; I have no financial interest in fitbit or equivalent, or strava.com or equivalent.]

Suppose that one would like to "register" some achievement on a leaderboard -- e.g., something like Strava.com.

Are there any crypto techniques that might be useful to make it harder to put up fake achievements?

Presumably, there are a minimum number of achievement fields that might be important:
name, address?, some-sort-of-id?, date of achievement, location of achievement, distance of achievement, time of achievement, etc.

Would it be possible to include certain hidden information -- e.g., address or SS# -- that would participate in the signature, but not be readily accessible to someone listing the leaderboard or even cryptographically verifying the claim?

One might want to log *witnesses*: witness1 signature, witness2 signature, etc.

As to date info, there are the usual *notary* issues, which might involve spending a microbitcoin to nail down the event time to a small portion of the bitcoin blockchain.

I would assume that the person claiming the achievement might have to cryptographically sign the achievement with his/her own PKI info; ditto for any "witnesses".

Perhaps one might want to include some sort of *signed photo* or *signed video* of the achievement.

Any other ideas of what evidence might be gathered and signed in order to "prove" the achievement?

Could any *equipment* be used as a witness?  E.g., could a mechanical *treadmill* or stationary *bike* (or other gym equipment) electronically sign an achievement?

Blood or DNA tests "signed" by the testing equipment??  :-)