Thorsten Engelmann will become the heaviest oarsman in Boat Race history when he competes for Cambridge University against Oxford on Saturday.
Engelmann was also part of the Cambridge crew last year
The 25-year-old German Olympian scaled 17st 6lb when the crews weighed in at London's Hurlingham Club on Tuesday.
Cambridge will be more than 9lb a man heavier at an average of 216.5 pounds, as they bid to prevent Oxford winning for the third successive year.
Cambridge President Tom James said he was "surprised" by his crew's weight.
He added: "It can be an advantage or disadvantage depending on the conditions."
Oxford president Robin Ejsmond-Frey agreed with his Cambridge counterpart's assessment.
"Being heavier is a mixed blessing," he said.
"It means they have some heavier guys but they also have to carry that weight down a very long course."
The race on the River Thames from Putney to Mortlake starts at 1630 BST on Saturday.
Oxford beat Cambridge by five lengths in difficult conditions in last year's event - their second straight win and fourth in the last five years.
Cambridge lead the overall series, which dates back to 1829, by 78-73, with one dead heat.
This year's race features the most non-British rowers in history. On their nine-man crews, Cambridge has five non-British oarsmen while Oxford has seven.
Oxford have four Americans, a Canadian, a Croatian and the first ever Pole to compete in the race, Michal Plotowiak. Cambridge have one American, two Canadians and the two Germans.
Crews for the 153rd Boat Race
Oxford: Michal Plotkowiak (Brasenose), Adam Kosmicki (Oriel), Andrew Wright (St Edmund Hall), Magnus Fleming (Worcester), Robin Ejsmond-Frey (Oriel), William Buckland (Jesus), Terence Kookyer (Keble), Ante Kusurin (St Catherine's), Nicholas Brodie, cox, (St Catherine's).
Cambridge: Kristopher McDaniel (St Edmund's), Dan O'Shaughnessy (St Edmund's), Peter Champion (St Edmund's), Jacob Cornelius (Emmanuel), Tom James (Trinity Hall), Kieran West (Pembroke), Sebastian Schulte (Gonville and Caius), Thorsten Engelmann (St Edmund's), Rebecca Dowbiggin, cox, (Emmanuel).