This is our digest of Dan Go's weekly 4 Minute Fridays newsletter — cutting-edge tips to get lean, boost energy, and live longer.

In this issue:

A fitness test that predicts how long you'll live
A new drug that prevents muscle loss on GLP-1s
The blood test Dan takes every 4–6 months

Dan opens this week on a personal note: he made an avoidable mistake by taking a shortcut instead of sitting down and doing the work — and got burned. His takeaway is that getting hit is part of pursuing anything worthwhile; the only truly expensive mistake is the one you never learn from. Don't complain or feel sorry for yourself — dust yourself off, extract the lesson, and let it push you forward.

Sponsor: This issue is brought to you by High Performance Founder Private Coaching — Dan's program helping entrepreneurs with 20+ pounds to lose drop weight and regain energy without giving up favorite foods or living in the gym.

1. The fitness test that predicts how long you'll live

Danish researchers followed a group of healthy middle-aged men for 46 years. At the start, each man's cardiorespiratory fitness was measured with a bike test — then the researchers simply watched what happened over the decades.

The results:

Men in the top fitness bracket lived almost 5 years longer on average than those in the bottom bracket.
The effect was a slope, not a cliff: every single-unit gain in VO2max bought roughly 45 extra days of life.
To rule out reverse causation ("healthy people just happen to be fit"), the researchers excluded everyone who died in the first decade — and the pattern held. Fitness looked like a driver of longevity, not a symptom of good health.

Dan's point: your doctor checks blood pressure and cholesterol every year, yet almost nobody measures VO2max — despite it being one of the strongest leading indicators of how long you'll live.

He's also running his own experiment: 30 days of daily cycling on an AI-powered bike, tracking VO2max, heart rate, and HRV — with results to be shared when they're in.

2. A new drug that prevents muscle loss

The known trade-off of GLP-1 drugs: fast fat loss, but research shows 25–40% of the weight lost on them is lean mass, not fat.

A new Phase 2 trial tested a possible fix. Researchers added apitegromab — an experimental drug that blocks myostatin, the protein limiting muscle growth — to tirzepatide in 102 adults with obesity. After 24 weeks:

Both groups lost about the same total weight.
The apitegromab group lost nearly half as much muscle.
85% of their weight loss was fat, versus 70% in the placebo group.

Note: It's early-stage research, funded by the drug's maker, and still years from approval. It also won't replace lifting weights. But it shows where GLP-1 treatment is headed: fat loss without wrecking your metabolism along the way.

❤️ Dan's favourite thing this week

One of the best things Dan has done for his health has nothing to do with training or nutrition: getting blood work every 4 to 6 months. You can look healthy on the outside and still be off on the inside — his own first panel came back with elevated HbA1c despite him feeling fine and looking the part. Blood work catches what the mirror can't.

For this he uses and recommends Superpower, a platform that runs a deep biomarker panel and turns it into hyper-personalized, AI-assisted recommendations. Readers can use the code DANGO for a free at-home lab test with membership.

Client of the week — Daniel, business owner

Daniel is an entrepreneur who struggled with his weight after years of putting his business first. In one year of coaching he lost 54 lbs (~24.5 kg) and reached his leanest physique since college. The approach:

Progressive strength training to preserve muscle while losing fat
A high-protein, nutrient-dense nutrition plan that fit his lifestyle
Sustainable routines that improved his sleep and recovery

The biggest factor, per Dan: Daniel stayed committed, trusted the process, and showed up consistently. Entrepreneurs who want the same can apply for the coaching program.

One quote to finish your week strong

"It's not about how hard you hit. It's about how hard you can get hit and keep moving forward. How much you can take and keep moving forward."

― Sylvester Stallone (as Rocky Balboa)

On the road to what you want, you will get hit — hard. That's part of the game. The people who make it are the ones who get hit, dust themselves off, learn, and keep moving forward.

──

As promised, get healthier in under 4 minutes.

— Dan

When you're ready, here are 3 ways Dan can help:

The Lean Body 90 System — reach your fitness goals on 90 minutes a week, without restrictive diets. 1000+ students.
Private one-on-one coaching for entrepreneurs who want to get lean, boost energy, and get in their best shape.
Sponsor the newsletter and reach 540,000+ subscribers.

References

Mandsager K, Harb S, Cremer P, Phelan D, Nissen SE, Jaber W. Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing. JAMA Netw Open. 2018;1(6):e183605. doi:10.1001/jamanetworkopen.2018.3605
Pratley RE, Denham DS, Trivedi R, et al. Apitegromab for lean mass preservation during tirzepatide-induced weight loss: a randomized, double-blind, placebo-controlled phase 2 trial. Nat Med (2026). https://doi.org/10.1038/s41591-026-04440-4

This is a summary digest of Dan Go's 4 Minute Fridays newsletter (July 3, 2026) — read the original here. This content is for informational purposes only and is not medical advice. Consult your healthcare provider before starting any new wellness protocol.

A Fitness Test That Predicts How Long You'll Live, a New Drug Against Muscle Loss & the Blood Work Dan Takes Every 4–6 Months