Paying attention to the overall picture when watching a race is one of the keys to staying successful in this sport and it's not just about trouble or bias or bad judgment by a rider.

Often times, when watching any telecast of a horserace, the commentors will refer to a horse not changing leads at an important stage of the race and if one can watch races intently, and view horses that have trouble changing leads, it could pay dividends at the windows.

Think of it like this. Your car is on the fritz and is at the local repair station. You need food for the company that will be on the way to your house in hours and there is no bus service or taxis.

So put on the sneakers and hoof it on out to the market. After shopping, and before the long trip home, you try to balance the groceries evenly in each hand but as the journey home continues, one side becomes heavier and you have to favor the other side of your body.

This is a bit similar to what happens to horses that don't change leads and it often happens when fatigue sets in or if there is something physically wrong.

Horses should run the straight-aways on the right lead and the turn on the left. They should swap leads as they start the turn and end it. It does require some coordination to do it and some horses find it hard to do when they are getting fatigued by the top of the stretch.

If you pay keen attention, you can see a runner struggling as he refuses to change leads.

In a perfect world horses can and will change leads on their own (they do it when turned out in a pasture, even as foals) but in a track setting they learn to do it when the rider shifts his or her weight sometimes accompanied by a slap on the shoulder and a tug on the rein.

Sometimes they don't swap, even when asked and then you'll see the rider stop shuffling about and just keep riding, figuring that he'll swap eventually. Usually if they don't change leads it's because they are getting fatigued and can't seem to figure out what to do with their legs.

Another human analogy that fits is this: You are walking carrying a heavy bag. You carry it in the right hand because you are right handed. You feel fatigued and shift it to your left and get a (short but sweet) burst of energy because you are no longer carrying the burden with tired muscles.

With juvenile racing just around the corner and with green inexperience horses that will race daily now is the time to understand how to pay attention to first time starters who run well but come up a little short while failing to change leads. If they do so next time that may be all they need to get up.

This is not to say that good horses always change leads, as one of the more famous runners to have trouble changing leads was the great Alydar.

Recently, on Sunshine Millions Day at Santa Anita, Carla Gaines trainee Red Sun won an entry level allowance race despite not changing leads and it was hinted at in the footnotes as the trackman wrote "Red Sun dueled, inched away, drifted out into the stretch, won clear."

Getting tired is one reason why a horse may have a hard time charging but failing to switch leads or, perhaps even more so, switching back to the left lead in the stretch is often a sign of unsoundness.

When a horse learns to rely on the lead change it can bring on renewed energy. The horse that comes to mind is Street Sense in his sophomore year.

Granted, it takes some training and careful scrutiny to watch a race with cash on the line and worry if a horse is changing leads or not but that is what replays are for and if you can identify one horse that was maybe green, didn't change leads, but comes back with good works since, that runner could light up the tote.