Boat Race: Rhythm of the Light Blues faces a stiff examination from heavy mob

"Internal fat is the great enemy of good wind," said Arthur Shadwell, Oxford's coach in 1846. Hopefully, his present counterpart, Sean Bowden, heeded such wisdom after the Dark Blues weighed in at a record average of 15st 7lb and a record stone and a half heavier per man than Cambridge for tomorrow's Boat Race, which starts at 3.05pm.

"Internal fat is the great enemy of good wind," said Arthur Shadwell, Oxford's coach in 1846. Hopefully, his present counterpart, Sean Bowden, heeded such wisdom after the Dark Blues weighed in at a record average of 15st 7lb and a record stone and a half heavier per man than Cambridge for tomorrow's Boat Race, which starts at 3.05pm.

Statistically, the heaviest crew has an advantage, but this massive crew has a slightly bigger hull in which to contain it, which will sit deeper in the water, thus giving their boat a greater wetted surface, which causes more friction. The scenario which has unfolded this week is Oxford to lead for the first third of the race before Cambridge grind them down, with the result depending on whether the big men's technical inferiority will shut them down before Cambridge lose the rhythm which gives them impressive boat speed.

Having said that, comparison of form, like most factors in the Boat Race - wind, tide, current, steering, and umpire's decisions - is not an exact science. This year, faced with probably the best two crews who have gone to the stake boat at Putney in the 175-year history of the race, the best we can do to forecast form is be picky with the stylistic detail.

Watch Oxford's bodies and you see every angle and awkwardness imaginable as these men, whose weights range from 14st to 16st 7lb and heights from 6ft 3in to 6ft 7in take stroke after stroke. Watch their oar blades, however, and they describe exactly the same arc, as precisely together as their body movements are subtly different.

Barney Williams in the two seat leans back markedly further than the rest in the manner of the Canadian Olympic crew that he came from, but his blade work is indistinguishable from the stroke-man Andrew Triggs Hodge, whose movement is easy and conventional. The bodies look stiff but when the power is turned on, there is no question that the boat's bow ball is reaching out to the finish line as the oars set up a chain of evenly spaced puddles.

Contrast Cambridge, whose height range is one inch lower and weight ranges from under 13st to 15st 7lb. They have a lucid, relaxed body language and stroke which turns on the moment after the blades rise from the water, where they poise, almost "til the cows come home".

A long, hard pull follows to send the boat away. The hull is as straight as an arrow. Off the stake boat yesterday they were sharp as an arrow, covering the bowman's puddles on the fourth stroke at a rate of 42 strokes to the minute. Oxford did not match this.

Both crews are stacked with international and Olympic talent. The difference is that Oxford are eight bruisers in a boat, while Cambridge are a lubricated, boat-moving unit. The other key factor tomorrow is the steering, especially if Oxford's Acer Nethercott is on the Surrey station. Nethercott coxed the crew that won by a foot in 2003 and the crew that lost by a clash last year, after which he unsuccessfully appealed to the umpire by claiming that Cambridge's steering was at fault. Since then, coxes and coaches from each side have given the umpire's panel conflicting accounts.

This year's umpire is Boris Rankov, professor of ancient history at Royal Holloway College, and he has endeavoured to teach Nethercott and Cambridge's Peter Rudge where he expects them to steer in their tussle for the best of the tide. But there is still a difference of interpretation between the Oxford and Cambridge experts as to where the centre of the tide - and therefore the centre of the course - lies. If either cox ignores Rankov, his ultimate sanction is disqualification, first (and last) used in 1849.

The forecast is an easterly wind of 10 knots or so which would be following at the start and finish, but a cross wave-rattling wind at the mile post and at the three-mile point.

Such conditions are unlikely to hinder or favour either crew or mar the race for that matter. So I expect Cambridge to lead by Barnes Bridge, when they can smell the brewery near the finish line, unless Oxford can butt their power advantage along for the whole, bruising four-and-a-quarter miles.