The biggest storyline for handicappers to consider every year heading into the Belmont Stakes is the distance. One and a half miles might not seem like much - and to casual fans it probably doesn't seem much different than the mile distance that is so common in horse racing. For horses, though, the Belmont distance is extremely long. It's almost certainly the longest distance they will ever run, and it's at least a quarter mile further than they have ever run before. There are no three-year-old horses in North America who are truly and completely suited to running this distance.

The job isn't to find the horse that will handle things perfectly. It's to be able to pick out the horses that will struggle with the distance less than others. When trying to determine how the distance will impact the Belmont Stakes, here are five factors to consider.

Does the horse have the breeding?: So much of what a race horse is capable of is determined by their mother, father, and the generations that came before them. To put things overly simply, if the ancestors of a horse was able to run a long distance effectively then chances are pretty good that the horse will be able to as well.

The analysis of pedigrees and their stamina potential is both an art and a science and can be a lifelong pursuit. For our purposes, though, there are shortcuts that can be taken.

For starters, look just at the sire (the father) and the damsire (the father of the mother, or the maternal grandfather). They have the biggest stamina impact. Did either of those horses win a Triple Crown race or place highly in one? Did they win a Breeders' Cup race? Was it a sprint or a longer distance? Have they had other offspring who have run effectively at longer distances?

You aren't looking for horses that have a proven record at a mile and a half because there just aren't enough races to make a meaningful sample size. Instead, you want to consider success in races of at least a mile and a quarter - the distance of the Kentucky Derby.

With a little bit of work with Google you can find the horses that make good sense to bet on and those that you should have legitimate concerns about because of distance limitations. Virtually every year you can find horses that deliver at nice prices because they are more suited for the challenge of the distance than the public expects. This year, for example, both Commanding Curve in the Derby and Ride On Curlin in the Preakness have finished second at nice prices, and both have pedigrees that helped them better than most horses in the races.

Has the horse outrun their pedigree already?: If a horse doesn't have an ideal pedigree for a Triple Crown race then you don't have to automatically toss them aside. This year provides a nearly perfect example of that. California Chrome's pedigree is a relative disaster. Neither side provides a whole lot of class, and stamina influences aren't in major supply, either. In the blue-blood world of high-level racing this is a decidedly blue-collar pedigree.

At this point, though, we can't be too concerned about that. In at least his last three races - the Santa Anita Derby and the first two legs of the Triple Crown - he has shown that he is a much better horse than he appears to be on paper. He is better than his pedigree.

Other horses might not be as extreme, but you don't need to worry, for example, if a horse is descended from sprinters if he has been effective more than once at longer distances.

How does the horse look in the stretch?: When evaluating distance limitations, the best thing to watch is the finish of longer races - like the Derby or even the Preakness. You can watch the videos online or even just look at the past performance charts. What you are looking for are horses that were moving forward in the closing stretches of the race or at least holding their position. Virtually all horses are slowing down significantly down the stretch, so horses that look like they are accelerating are often actually just ones that are able to hold their speed.

If a horse is strong down the stretch in a long race then it makes sense that they could be reasonably effective in an even longer race. The top two finishers in each of the two Triple Crown races so far have been moving nicely in the closing seconds, and there are other solid performances hidden in those races, too.

What is the race likely to look like?: As a general rule, the faster a horse is forced to run early on in a race, the tougher it is going to be for him to finish strong at the end of a long race. If a horse likes to be on the early lead, then, he could be in trouble if there is expected to be a speed duel in the opening fractions, but he could be in great shape is he is likely to be able to set a slow, comfortable pace early on.

By putting some time into thinking about how the race is likely to be run, you can have a big edge in understanding the impacts of the Belmont distance.

Has the horse handled adversity?: The horses that shine at the Belmont Stakes are often the toughest, feistiest horses. They are going to face a whole lot of adversity, and their ability to deal with that will determine their success.

The best way to tell how a horse will deal with the adversity is to see how they have dealt with it in the past. Looking through past performances or old news stories for particularly trying challenges - a bad trip, poor track conditions, and so on - and how the horse responded can help you rule out horses who aren't likely to respond well.

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Read more articles by Trevor Whenham