After decades of swearing by workout classes, I switched to weightlifting. I never expected to be so impressed by the results.

Tech Insider : Business
Alexandra Frost and her partner selfie
After doing workout classes for decades, I decided to switch to a strength-training program.

Alexandra Frost

'Strong is the new skinny': Women leaders are strength training to thrive at work

Tech Insider : Business, Environment, Sports
Anne Marie Chaker
Veteran journalist Anne Marie Chaker said strength training sharpened her focus, confidence, and creativity at work.

Stella Kalinina for BI

When Deb Stern steps up to the barbell for a heavy back squat, all distractions fall away.

Can't do a pull-up? This Marine colonel told us how to get your first rep

Tech Insider : Business
Marine corps colonel Misty Posey's pull-up program has become a popular method for some Marines hoping to boost their reps.
Marine Corps colonel Misty Posey's pull-up program has become a popular method for some Marines hoping to boost their reps. Here, Posey, far left, coaches some students.

Lance Cpl. Cody Fitzgerald/US Marine Corps

I'm the president of Orangetheory. As an introvert, I rely on 2 breaks in my workday and an acupressure mat to recharge.

Tech Insider : Business, Environment, Travel
Orangetheory president Lauren Cody
Lauren Cody, president of Orangetheory, travels twice a week and said her routine is all about balancing exercise, nutrition, and sleep on the go.

Courtesy of Orangetheory

We asked a personal trainer how he would spend $100 on supplements. Here's what he bought.

Tech Insider : Business
A man shopping for supplements in a store aisle.
Shopping for supplements can be overwhelming.

Charday Penn/Getty Images

I took my first in-person Peloton class. It felt like an exclusive event — which was the point.

Tech Insider : Business
Two women in a Peloton class
I took an in-person Peloton class with Jess King. I appreciated how intentional every detail was.

Joi-Marie McKenzie

Superpower wants to make you hotter, smarter, and healthier

Tech Insider : Business, Economy, Technology
Max Marchione
"When a peptide is legal, we are going to sell it," says Max Marchione, Superpower's cofounder and CEO.

Christie Hemm Klok for BI

I adopted a new fitness strategy in my 40s that's helped me run half-marathons, hold handstands, and do pull-ups as I age

Tech Insider : Business
Lorraine C. Ladish doing pull-up in park
I started setting physical goals for myself in my 40s, including pull-ups and handstands.

Lorraine C. Ladish

I'm 77, and I discovered my love for running while serving in Vietnam. Now I work out 7 days a week.

Tech Insider : Business
A senior man on a bicycle, wearing a helmet.
Winston Hall on one of his cycling expeditions.

Courtesy of Winston Hall.

I'm the CEO of Klaviyo. I run on a 'creator-type' schedule and love Diet Coke and country music.

Tech Insider : Business, Sports, Technology
headshot of a man in a gray shirt next to a bookcase
Andrew Bialecki.

Courtesy of Klaviyo

This as-told-to essay is based on a conversation with Andrew Bialecki, the 40-year-old CEO of Klaviyo, based in Boston. It's been edited for length and clarity.

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