For most of the last 15 years in the UFC, the structure of weigh-ins before events has been the same. This weekend will be different.

The California State Athletic Commission (CSAC) has shaken things up with its emphasis on changing the culture of using severe dehydration to cut weight in MMA. In February, the CSAC passed ground-breaking rules that have already been adapted in other commissions across the country.

UFC 199 in Los Angeles will be the first UFC event where the new regulations will be applied. The card is the first of what could end up being the norm in the sport moving forward. The UFC itself is already considering changing its weigh-in procedure.

A full breakdown and answers to all the pertinent questions about the rules are below.

What exactly are CSAC's new weight-cutting rules?

The biggest change will happen Friday. Beginning at 10 a.m. at a nearby hotel, the athletes can begin weighing in. They will have a window of four hours to do so and can hit the scale at any time during that period. UFC and commission officials will be present. That's a major difference from the typical 4 p.m. weigh-in. The idea is to give fighters more time to rehydrate before the fight.

In addition to the weigh-in change, doctors on hand Friday and Saturday during fight night will pay closer attention to hydration while examining fighters. For the first time, doctors will have the ability to use specific gravity tests on fight nights to determine if a fighter is adequately hydrated to compete. If a fighter is still severely dehydrated on fight day, the commission doctor could pull him or her out of the fight for safety reasons.

What will happen to the regular, television weigh-in fans are accustomed to?

It won't go away and will largely be the same, according to UFC vice president of public relations Dave Sholler. It will remain at 4 p.m. Fighters will still pose on stage and square off with each other like the weigh-ins we're used to. The only difference will be that Joe Rogan will announce the weights that were previously recorded rather than the ones read from the scale right then and there.

The 4 p.m. weigh-in will be open to the public and air on FOX Sports 1, as usual. The official weigh-in earlier in the day will be closed to the public and media. CSAC executive officer Andy Foster said because there will be medical exams going on in the same room during the official weigh-in, they cannot be public events. Foster said that part of the procedure might change in the future.

What happens if a fighter misses weight and how will anyone know if he or she does?

Pretty much the exact same thing. Once a fighter declares it is his or her official weigh-in between 10 a.m. and 2 p.m., the typical protocol will take effect. If a fighter misses weight, he or she will get a second try as always. If the weight is still off, the one-hour window to make weight applies. If the fighter is still more than a pound after one hour, 20-percent of his or her purse will be forfeited. The rules in this regard have not changed.

If an athlete misses weight, how will anyone know? Well, a representative from the opponent's team will be called down to witness the weigh-in to ensure transparency. The UFC will announce the official weights at their TV weigh-in at 4 p.m. and the commission will have the weights available as public record thereafter.

Should we expect dehydrated fighters to be pulled from the card?

This is the question every fan keeps asking. Short answer: No, probably not.

Association of Boxing Commissions vice president Dr. Edmund Ayoub told me in April that he did not foresee any fighters being yanked due to the new regulations. Ayoub has been integral in helping CSAC executive officer Andy Foster and chairman John Carvelli come up with the weight rules and said he has no interest in seeing fights being lost.

Ayoub said if a fighter is severely dehydrated on weigh-in day, he will be given a plan to rehydrate properly in time for the fight. If that fighter is still severely dehydrated on fight day with no more time to replenish nutrients, then and only then will he or she be prevented from competing.

"The goal here -- and this is important -- is not to disqualify a fighter," Ayoub said. "The goal here is to change the thought process that losing massive amounts of weight and getting to a lower weight class is going to make you a better fighter. Because it absolutely unequivocally is going to do absolutely the opposite. But there's still a mindset here."

How does a doctor know if a fighter is dehydrated?

According to Ayoub, there are a few indicators. Those include heart rate, blood pressure and skin turgor. If a fighter has a high heart rate, low blood pressure or a lack of skin elasticity, that's a red flag. At that point, a specific gravity test can be used on fight night to test for hydration level. A combination of all these things will determine if a fighter is severely dehydrated.

What's the fuss about dehydration anyway?

Many experts think the way fighters cut weight is the biggest issue in MMA today. There is a long-held belief in the sport that the more weight a fighter can cut, the better and bigger fighters have an advantage in the cage. Fighters can lose 30 pounds or more to reach their weight class and a popular method is through severe dehydration.

The problem with severe dehydration is that it's dangerous in a vacuum and even scarier for someone who is going to get punched in the head a few hours later. Ayoub and his peers believe that a fighter cannot be fully rehydrated -- especially in the brain -- just 24 hours after depleting themselves of all those necessary fluids and nutrients. That can lead to an increase in concussions and beyond. Moreover, Ayoub thinks performance also suffers and that there is an advantage in being the bigger fighter through dehydration is a myth.

"There's this underlying push from promoters and belief from fighters that, 'If I can lose weight and be at a lower weight class than I normally would be, I'm gonna be stronger,'" Ayoub said. "That's a myth and it's absolutely wrong. I need to get people to change that thought."

How do fighters feel about all of this?

Mixed bag. No fighter out there likes cutting weight. It's one of the worst parts of the job, probably the worst. But few fighters think weight cuts are a major problem, mostly because they believe there is evidence that being the bigger fighter in an MMA competition is indeed an advantage. And fighters will always try to gain an advantage no matter the cost. Cutting weight is a process that originated in amateur wrestling and the culture has stuck.

There is a belief that fighters must be convinced that their performance will suffer due to extreme weight cutting and that's the only way things will change. Fighters, warriors that they are, value performance over long-term health. So far, they have not been convinced that cutting weight hurts them in fights and many believe that specific gravity tests and examining for dehydration is bunk. Most fighters are fans of the status quo in this regard and understandably want a say in changes made that will affect their livelihood.

What fighters do love about CSAC's new rules is getting to weigh-in earlier with more time to rehydrate. Dominick Cruz spoke about it during a recent episode of UFC Embedded. Luke Rockhold addressed it on The MMA Hour with Ariel Helwani on Monday. In the typical weigh-in procedure, fighters must stay on weight for hours waiting for the 4 p.m. weigh-in show. Not in California this week. They can wake up, cut the rest of the weight, step on the scale and they're done. They can begin eating and drinking again.

"I'm excited about the weigh-in early," Rockhold said. "I think it's stupid to sit there and deprive yourself and wait for all this bullsh*t to go through and stay dehydrated and let your body keep sucking fluid from your brain. It's that downtime. Once you've made the weight, what's the point of sitting there just to please everybody? The PR side of things. It's not healthy. I think it's smart on their part."