Conor McGregor's weight cut

Conor McGregor has made weight at 145, 155 and 170 in the UFC. For anyone who cuts weight, the most useful fight in that record is the one where he did not cut at all.

The scale record

Read the results column with care. Opponents, age, long layoffs and two leg injuries sit in it too, and none of them can be separated from the weight. What the weigh-in column does show is what no cut looks like: in his first 2 fights at 170 he weighed in 2 pounds under the limit.

The method his nutritionist described

George Lockhart, described by ESPN as his longtime nutritionist, ran the cut for the Aldo fight. Afterwards he said McGregor and his coach, John Kavanagh, saw it as the easiest cut of McGregor's career. A teammate, Gunnar Nelson, described the 145 cut differently later in 2016, as a hard one he did not think McGregor wanted to repeat.

Before UFC 229 in 2018, Lockhart laid out the structure on a podcast. Water goes up about 10 days out, with sodium kept high. Sodium comes down about 3 days out. And in fight week the fighters eat more, not less. He also said McGregor's walk-around weight and body fat had barely changed in 3 years.

That order matches the staged approach the research supports: a water load early, sodium reduced late, and as little as possible left to sweat. How the stages fit together.

For the Mayweather boxing match in 2017, Lockhart told ESPN the day before the weigh-in that McGregor had woken up 8 pounds over the 154-pound limit and would be at about 156 by that night.

The fight with no cut

In February 2016 his lightweight title fight with Rafael dos Anjos fell through when dos Anjos broke his foot. Nate Diaz took the fight on 11 days' notice, and it was set at 170, 25 pounds above the division McGregor held the title in.

He weighed in at 168. A few months later he explained to ESPN what had changed. With no cut to make, he stopped working with Lockhart, and for the final 2 weeks he ate what he wanted. He had far more energy than he was used to when cutting to 145, and he spent it: swinging on gymnastic rings in fight week, doing so much bouncing footwork that the balls of his feet were burned. The first 8 minutes went his way, he said. Then his gas tank went, and Diaz submitted him in the second round.

He brought Lockhart back to work year-round, including for a 170-pound fight in which he would cut nothing. For the rematch in August he weighed 168 again and won a majority decision.

My reading, from the outside: the cut had been doing a second job. It fixed the structure of his fight week, what he ate, when he rested and what training he did. When the cut went, the structure went with it, and the surplus energy was spent in the wrong places.

Moving up still needs a plan

Fighters move up to escape a cut, and often it is the right call. What the 2016 fight shows is that fight week still needs a plan once the scale stops enforcing one: food, rest and fight-specific training decided in advance. What changes when you move up, and how fight day itself is fueled.

Choosing the division is still the first decision, and the calculator shows what a given gap means at your own weight.

Common questions

Who is Conor McGregor's nutritionist?

George Lockhart, described by ESPN as his longtime nutritionist. He ran the cut for the José Aldo fight in 2015 and worked with McGregor for the 2017 Mayweather boxing match and for UFC 229 in 2018.

What did Conor McGregor weigh for Nate Diaz?

He weighed in at 168 pounds for both fights, which were contested at 170. Diaz weighed 169 for the first and 170.5 for the second.

Why did Conor McGregor stop fighting at 145?

He never framed it publicly as a single decision. After winning the featherweight title in December 2015 he fought at 170 and 155, won the lightweight title in November 2016 and never returned to 145. A teammate said in 2016 that he did not think McGregor wanted to make the 145 cut again.

What did Conor McGregor weigh for Max Holloway in 2026?

He weighed 170.5 pounds for their welterweight rematch at UFC 329 on July 11, 2026. The fight was stopped at 1:09 of the first round after he injured his knee. Holloway weighed 170 for the same fight, and his own case study covers the cut.