Soccer, in particular, precluded quite a number of shapes and sizes.

Fortunately, rugby offered refuge to some.

Fatties (props), lankies (second rows), and maladroits (blindsides) could reinvent themselves and follow their dreams.

That is one of the glorious elements of rugby union . . . its universality. The game is allpurpose and accommodating, no matter your shape or size.

It's why rugby league doesn't have the same appeal to me . . . you have 13 homogeneous units playing the same game. They are all 5'10" and 16 stone. They all do exactly the same thing on the pitch and it is a distinct disadvantage to be any taller or heavier than the mean indicated 5'10" and 16 stone.

It is something I have observed over the years, not so much with regret, but with resignation . . . the metamorphosis of union players into a more homogeneous product as the body shape changes.

This piece might get a little bit technical but it's still worth the read because some of the information is startling.

Essentially you have three body types: 1) Endomorphs, 2) Mesomorphs, 3) Ectomorphs.

Endomorphs are the chunkies, plumpies and fatties; mesomorphs are standard issue all the way up to Arnie types, and ectomorphs are beanpoles all the way up to Peter Crouch.

I would have been an ecto/meso apparently.

Not quite sure what I'd be classed as currently, but I'm sure there might be a little bit of endo in there right now.

What we want to do is a small bit of comparative analysis between things, say, at the end of the amateur era and things as they are now . . . the reasons behind the body shape change over the years.

The national squads' physiological and conditioning management programmes and philosophy are staggeringly focused and effective. It's a simple equation. Rugby union is a game of power and pace. The team which has the most powerful performers will be in the ascendancy. The All Blacks have a squad of 45 players who collectively are more powerful than any of the other teams in world rugby. The programme demands that the Irish squad therefore try to maximise muscle mass content. It's a tricky thing to do because it has a negative effect on speed, so year on year you look for equilibrium.

It seems that the way to progress through a systematic weights programme is to add muscle mass slowly. It gives the new muscle fibre a chance to adapt. The greater the foundation of preparation, the better the ability of the athlete to optimise the additional muscle bulk.

This could mean though that a rugby player's prime could come two to three years later down the line. Normally, a centre three-quarter's shelf life would be 30-31 with a prime of 27-29. If the muscle bulk is being acquired slowly as instructed, a centre could now . . . at the highest level . . . have a prime say at 30-32 and a shelf life until 34.

As I have already mentioned, it is a tricky one. In the race to lower body fat ratios and increase muscle bulk, you can interfere with your androgynous hormones by lowering your body fat or dietary fat compositions, thus lowering your body's ability to produce testosterone, the male hormone which is the prime constituent in your body which produces muscle fibre. It's a slow race to the top of the pyramid.

The parameters are already impressive.

Body-fat ratios in the squad are as follows:

Front row 14-17/18%, second row 10-14%, back row 8/9-14%, halves 8-14%, three-quarters 10-14%.

In my prime, my body-fat ratio was 23%. I would have been 100+% above the required average. One of the current Irish halves is below 8% which is staggering. In the early '90s a scrum-half who just has to remain nameless had a body-fat ratio of close to 40%. It's a fact!

Now you see why body shapes are changing.

Back to the All Blacks . . . the All Black squad range of body weight does not extend out of the 90kg-110kg bracket. Ireland's varies from 78kg-126kg. The All Blacks range seems to be the optimum range.

These guys have low centres of mass and even lower centres of gravity, and as the pro game changes these guys become more difficult to knock over or tackle and picking tall men to try and tackle these men isn't an option . . . you have to pick 5'10" 16-stone guys to stop them . . . the shadow of homogeneity begins to appear.

Squad members' bodies must be geared towards tolerating the hits. But as the years go by, the hits become harder and the self-perpetrating cycle increases again. Increase muscle bulk to withstand hits . . . hits become harder as a result of higher muscle bulk.

To give you an idea of how far the pro game has progressed, chew on this statistic. Nobody has really been able to quantify how much stronger the pros are than the good ol' boys in, say, '95/96.

In 1996, the best one repetition max for a squat was 150kg (330lbs); as we enjoy our Sunday, the pros in Spala were squatting as close to 300kg (660lbs) as makes no difference.

Liam Hennessy, the IRFU physiological and conditioning guru, has stated that strength levels have increased by 100%. Given the stats, you can't really disagree. The pros are lifting 100% more than the international players 10 years ago.

The muscle mass in pro play has increased incrementally . . . for every kilo of muscle there is an 8-10kg strength increase.

Imagine Seamus Dennison's famous tackle on Stu Wilson when Munster beat the All Blacks in 1978. Wilson was hit with a tackle of real fury and venom. But he managed to get up. If it happened today, they could leave him there and just erect a gravestone.

Changes in body shape and strength also require a dietary perspective. Most nutritionists would state that a daily calorie intake for an average male would be somewhere in the region of 2,100-2,400. The Irish squad in the period 1996-1998 would have had a calorific intake of near enough 5,000 on a per diem basis. That's a lot of calories . . . a lot of eating to get through.

Liam Hennessy stated that during the Spala sessions, which were part of the 10week 'rest', most of the forwards would have had an intake of 9,500, which is staggering.

You would have to spend a large part of the day just eating . . . like a sumo wrestler. It's a fairly dour regime . . . work out, eat, rest, work out, eat, rest. I wouldn't fancy having to chug these protein shakes and isotonic drinks day in, day out.

Is it dangerous to consume that much?

Not really, if the intensity of the sessions is as gruelling as they are. But when a few of the lads fall off the conveyor belt, it will be hard for them to readjust down to even '96 levels.

It is sad in one sense that at the top level the dictats of the professional game mean that there are no more props like Martin Cahill and Jimmy Screen any more. Malcolm O'Kelly could be the last of his type as union goes absolutely meso. In 20 years' time we will have 15 players who all fit the same body profile as Brian O'Driscoll . . . 5'10" and near enough 16 stone.