4. Sylvester Stallone's Rocky Health

Sylvester Stallone seriously injured himself on numerous occasions whilst filming the Rocky movies. The actor insisted on actually taking punches in order to make the action seem more realistic.

The result? Stallone has, according to StyleBlazer, heart problems as a result of the injuries he suffered whilst filming Rocky IV.

Sylvester Stallone
Stallone suffered heart damage as a result of taking punches during filming.