The most common and most likely answer to this crossword clue is the 9 letter word DECATHLON
I've seen this crossword clue in The Daily Telegraph
D
E
C
A
T
H
L
O
N
More clues leading to the result DECATHLON
- Ten events the old can fancy
- Cook latched on to competition involving various disciplines
- Latched on to jockey — it’s eventful!
- Sporting event strangely not held outside California
- Competition in foreign chalet overseen by academic
- Sporting contest put on outside chalet in resort
- Told he can become involved in an Olympic event
- Chat with Noel about taking on Germany in athletic event
- Sporting event halted on ground around college
- Multiple events, then a cold snap
Buddy explains!
The straight part
We know that "that requires much athleticism" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case that requires much athleticism = decathlon.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DECATHLON mean?
DECATHLON noun- An athletic contest consisting of ten events which includes sprinting, hurdling, jumping, and throwing over a span of two days.
- A contest in science and math proving skill.