If you took a look at Jennifer Aniston, you would not think she is 49 years old. She is in incredible shape, not just for her age but for any age! If you've seen her in Just Go With It or We're The Millers, you'll know what I'm talking about. You can't help but notice her slim and toned arms. Her secret to achieving her sculpted arms is boxing!

Jennifer Aniston (left) in the movie Just Go With It

Jennifer gave her fans a bit of insight into her workouts in the September issue of InStyle. Jennifer said that before she discovered boxing, she was committed to yoga. She now says that boxing is her "exercise of choice".

"Last year I discovered boxing, and I love it. I have this trainer named Leyon, who I believe hung the moon," she joked during the interview. She said that boxing is the "longest workout [she's] actually stayed with consistently other than yoga".

"There's something about the mental aspect of boxing — the drills, your brain has to work, you're not just sitting on a bike. It's amazing," she said. Jennifer said that she loves boxing because it helps her get her aggression out. "You get a mental release of all this crap you're taking into your ears and eyes every day and have little fantasy moments imagining who you're actually punching. I'm just grateful it's not actually the person, even though there's one person. You know what I mean. It's all good," said Jennifer.

Other Stars Who Box

Jennifer isn't the only star that is boxing to stay fit. Other celebrities like Khloe and Kourtney Kardashian and Gigi and Bella Hadid also love the workout. Many models and celebrities have started boxing to get their bodies in tip-top shape.

Gigi Hadid, model

Gigi Hadid said that she uses boxing as a stress reliever. "When I walk in [to Gotham Gym], it's like my big brothers. They don't care about me as a model or what my body looks like. They care that I give a good punch, and that's how I want to be judged in my athletic space - because that's what I find pride in." Gigi also told Vogue "When you're boxing, you get so into it mentally that you kind of forget what's going on, you forget that you're working out."

Bella Hadid, Gigi's sister, said that boxing is great for creating washboard abs and sculpting curves. Ellie Goulding, pop singer, said to Well + Good that boxing has helped her find inner power: "I found inner confidence [through]: boxing and kickboxing. I love that extra kick of adrenaline. Keeping fit doesn't mean spending hours at a gym; the key is to find a workout you really love."

Ellie Goulding, singer

Dayne Williams, professional boxer, spoke to Now to Love about the benefits of boxing. "Boxing offers a high-intensity cardiovascular workout. And when performed with the correct technique, boxing will stimulate musculature in the whole body as you use your footwork to move in and out to punch - be it on the bag, trainers pads or a sparring partner".

"Because in boxing you are repetitively moving the ankle, knee, hips, and shoulder joints, you will be stimulating all the muscles crossing these joints and effectively building muscular endurance," said Williams. "With multiple muscle groups being stimulated your heart beats faster to bring oxygen to the muscles, hence the cardiovascular workout".

Never Boxed Before?

You shouldn't be afraid to try this sport. Some people think that it's only for professionals or that it's too dangerous. This isn't true. "Contrary to popular belief boxing is actually a very safe sport to learn. A good boxing coach will teach you step by step. Focus on learning technique and even try training up for a beginner fight - then you will do real boxing workouts," said Williams.

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Health Benefits

Aside from the obvious benefit of obtaining a strong and lean physique, boxing also offers similar benefits to other cardiovascular exercises like running, cycling, and rowing.

"Much like how running burns a lot of calories, so does boxing. Boxing also has periods of high intensity - it offers all the benefits that high-intensity interval training does. For those looking to lose weight, that means an increased metabolism following boxing workouts," said Williams.

"Along with weight loss, boxing offers improved cardiovascular and muscular endurance, increased lean muscle... and when people learn boxing their confidence goes through the roof - with all the punching you will be doing, it really is the perfect stress reliever," William said. Boxing is different from other workouts that you may do using gym machines because it offers variety. You aren't sitting at a machine doing the same repetitive movement over and over again.

"And when you become a part of a boxing gym you get access to a new community that can't be found in an ordinary gym," Williams added. Boxing isn't only used for exercise. It can also be used for self-defense, building confidence, and improving athletic ability.

William concluded the interview by saying: "I recommend everyone take up boxing regardless of your goals. Especially those who do not think boxing is for them as often they are the ones who need it most."

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