When I answered the phone, the Arnold Schwarzenegger-like voice on the other end said, with genuine relief: “You’re alive! I thought I was going to open the paper, and read, ‘New York Sun Reporter Drops Dead After Workout.'”

It had been three days since my hour-long training session with Vienna-born fitness expert Stefan Aschan, and he was calling to make sure I hadn’t subsequently gone into cardiac arrest.

Though I never felt like I was at death’s door, Mr. Aschan, the president of a New York-based company, Strength 123, did provide a humbling total-body workout — all without weights, body bars, or equipment of any kind. Mr. Aschan, who moved to New York from Austria a decade ago, insists that you don’t need a gym membership or traditional exercise props to embark on a new, body-changing fitness regimen. He advises using your environment and its existing resources to create a personal gym, of sorts: If you’re at home, use the chairs, stairs, and towels; if you’re outdoors, use the hills and park benches. For his workout video “Strength 123” — which includes two, nearly hour-long sessions — all you need is a sturdy chair (for triceps presses and pelvic lifts) and a mat or a towel (for floor work, such as leg lifts, abdominal exercises, and modified pushups).

While this city is home to gyms and exercise studios of all stripes, many New Yorkers gripe that there simply aren’t enough hours in the day to get there — given their family, work, and social obligations. Mr. Aschan said his busy clients “don’t want to waste time going to the gym, and waiting in line for machines, when they could have used this time more efficiently by working out at home.” Or outside, even during the cold-weather months, if they’re appropriately bundled.

For our early-morning training session, Mr. Aschan suggested we brave the chill, and meet at a West Side entrance to Central Park. There, our session began with a circuitous, 10-minute run — not a jog — to a hilly incline, not far from the Sheep Meadow. We did some stretching, followed by a series of sprints and skipping exercises on a steep park incline.

“Bravo, G-aaah-brielle, bravo,” he cooed, each time I made it to the top of the grassy hill. The whole scene was evocative of “The Sound of Music,” with me skipping uphill as a jovial, blond Austrian was cheering me on. By that point, though, I was so out of breath that there was no chance of a “Do, Re, Mi” rendition.

Next came a short rest — when I was finally able to catch my breath, albeit briefly — followed by a seemingly endless series of squats, lunges, and fluttering arm movements. Then there were triceps dips, done while holding on to a park bench, and leg lifts done atop a knee-high concrete step. These exercises had me resisting only my own body weight “so you will learn proper execution of the movement, form, and prevent injuries,” according to Mr. Aschan. With more advanced clients, Mr. Aschan might bring a gummy band or a medicine ball into the mix, but insists these items are not necessary.

Versions of the prop-free, muscle-fatiguing squats, lunges, flutters, and triceps presses are all on the “Strength 123” DVD, which he handed me as our meeting was coming to an end, and when I was about ready to plotz. As I was catching my breath during the coo-ldown, Mr. Aschan gave me a brief explanation of the 14-day, customized “Mental Detox” nutritional program he developed as a companion to his workout regimen. The basics: a diet that comprises almost no sugars, no caffeine, no processed foods, and no yeast.

Two days after training with Mr. Aschan, when the soreness in my triceps and hamstrings had dissipated, I attempted the DVD workout. It was a challenge reminiscent of my recent Central Park sweat fest, but one that has felt decidedly more manageable with each play. The fourth, and most recent, time I exercised to it, 55 minutes flew by in what I would have sworn was half that time.

Personal training sessions start at $150; group and corporate rates are also available. The “Strength 123” workout video is available on DVD for $29.99, or via podcast for $19.99. Through January 10, the “Mental Detox” program fee is $297, which includes six weeks of diet coaching. More information is available at stefanaschan.com.