T hese days, as soon as an athlete passes the age of 30, they are put into the bracket of 'getting on a bit'.

By 35, they are considered to be positively geriatric. The general opinion is that a sportsperson in their mid-30s is living on borrowed time and you can guarantee that every single article written about them will mention their age as if the detail is of paramount importance.

So when Ryan Giggs celebrated his 40th birthday last week, having played more than 1000 games of professional football for Manchester United and Wales, the plaudits came in their droves.

Giggs is one of the few athletes whose powers do not appear to have waned significantly with the passage of time, but he is not the only one. Serena Williams has had her most dominant season this year despite turning 32, and in regaining the world No.1 ranking in February, she became the oldest to do so in WTA history. Sir Chris Hoy was 34 when he won his final two Olympic gold medals at London 2012 and Chris Horner became the oldest winner of any of cycling's Grand Tours when he won the Vuelta a Espana in September at the age of 41.

But should we be so surprised that more and more elite sportspeople are lasting longer than we think should be possible?

Professional athletes are treated like royalty these days. Every aspect of their life is monitored and then each action is calculated in order to extract maximum performance from their bodies. It is hardly surprising, therefore, that said body is relatively well-preserved into their thirties and beyond.

There are, of course, some athletes whose bodies break down irretrievably and for them, retirement is the only option. But in modern-day sport, support staff are so intertwined with an athlete's daily regime that it should not be considered particularly surprising that a 30-something-year-old can compete with athletes a decade younger than themselves.

Sports scientists and physiologists devise physical sessions which focus on quality rather than quantity. A body over the age of 30 cannot cope with the workload of a 20-year-old, but training smarter can often be far more productive than just putting in the hours. An athlete who has 15 or 20 years of hard training in their legs has such a solid base of fitness and an ingrained skill-set that an excessively heavy workload is often of little benefit. Physios and masseurs rub, tape and acupuncture an athlete's body in order to prevent and heal injuries. Nutritionists advise the athletes on their diet to help them fuel their training sessions and ensure optimum recovery afterwards.

What is quite astonishing, however, is the ability to sustain the mental fortitude required to compete at an elite level for such a prolonged period of time. The mental strength witnessed by observers each time an athlete competes is just a tiny fraction of the resilience which is needed to scale the heights of elite sport. In fact, the most draining aspect of being a top athlete is the training.

To push your body to the limit day in, day out is about as much fun as poking yourself in the eye with a sharp stick. On occasion, the stick would be the more palatable option.

Giggs and Hoy and all the other athletes whose 30th birthdays are in the distant past, have lived such disciplined lives for their whole careers and this self-control is not easy to maintain.

The list of sacrifices is endless, although most who pass up the chance of a 'normal' life for that of an athlete do not see it as a sacrifice. By the time a sportsperson has dragged their body, kicking and screaming, into their 30s, the list of injury problems racked up is usually lengthy.

So to maintain the motivation which is required to continually push through the daily aches and pains, the omnipresent soreness and the dull ache of tiredness, is mightily impressive.

The majority of athletes who continue competing when their peers have retired are not doing it for the money. Giggs presumably has more money than he knows what to do with, so an extra couple of seasons are neither here nor there for him financially. Athletes continue beyond the expected timescale for the love of their sport, and that is why they are so revered.

The praise directed towards Giggs was on a scale rarely seen for players pre-retirement. And while his longevity has been enabled by his physical prowess, it's the mental capabilities of an elite athlete well beyond their 30th birthday which should be so admired.