Will Smith gained a pound instead of losing weight after a week of hard workouts. That doesn’t mean his program failed, trainers say.

• Will Smith said he initially gained a pound in his first week of intensive workouts to lose weight.
• But weight changes can happen for a variety of reasons, and they don't mean your program is a failure.

Actor Will Smith shared his fitness routine on a new YouTube series, and said he struggled at first to lose a single pound after working out hard for a week.

The actor actually gained weight when he first started trying to get fit, according to the first episode of his new series "Best Shape of My Life," which debuted on his YouTube channel November 8.

Smith said his initial goal in January 2021 was to lose 20 pounds in 20 weeks after the pandemic had left him in "the worst shape of his life." He started an intensive diet and exercise program, which included daily runs at sunrise, as well as resistance training with weights at least four days a week.

But when the actor weighed in after the first week, he had gained a pound, instead of losing weight. Smith responded with two days of eating almost nothing but boiled eggs and raw vegetables, he said in episode two of the series. After his trainer convinced him to stick to the program, however, he was back on track and started to lose weight.

Instead of panicking about short-term fluctuations, stay consistent to get long-term results, fitness pros and dietitians say.

If your weight loss is stalled, be patient, experts say

Changes to your body take time, whether that's building muscle, losing fat, or both, which is why it's so important to stay consistent with an exercise program or diet to see results, experts say.

If you are hitting a fat loss plateau, you shouldn't bail on a program or make dramatic changes after just one week, Bonnie Taub-Dix, registered dietitian nutritionist, previously told Insider.

"You don't have to be more strict, you have to be more patient," she said.

Weight isn't the only measure of fitness progress

Many factors that influence your weight have nothing to do with body fat, including how hydrated you are, what you've eaten that day, or what time of day it is.

As a result, the scale isn't always the best indicator of whether you're making progress, particularly short-term. A more helpful way to measure fat loss over time is to weigh yourself at the same time each day, and calculate the average from week to week to notice any changes.

You can also measure fitness progress, regardless of aesthetic or weight changes, with benefits like having more energy, strength, and stamina.

Weight increases aren't necessarily a bad sign for your fat loss efforts, either. If you're new to fitness or getting back in shape, you may experience body recomposition, or gaining muscle as you lose fat, which means the scale may stay stable or even go up.