Gyms | Mill Valley | Testimonials | Fitness

The Strength Den has completely transformed my relationship with strength training. As a former competitive athlete (volleyball, basketball, tennis), I’ve always loved training — but chronic shoulder and hip impingement issues made lifting consistently nearly impossible throughout my twenties and early thirties. I’d try to get back into it, only to end up sidelined by pain. I’d been through several rounds of physical therapy, tried dry needling, massage therapy — nothing ever really stuck. Two years ago, I couldn’t squat a 30lb dumbbell without flaring up.

Then I joined The Strength Den — and everything changed.

What makes this place special is how truly personalized their approach is. This isn’t a “one size fits all” gym. From day one, the coaches took time to understand my history, my limitations, and my goals. I started working with Ada (their in-house physical therapist), and together with the trainers, we built a smart, individualized, progressive program that helped me get stronger in all the right ways. Over time, I was able to train consistently, without pain, and actually start progressing again.

Yesterday, I hit lifetime PRs: 315lb squat, 205lb bench press — something I never thought I’d be able to do.

This is an incredible gym for anyone serious about getting stronger. Whether you’re just starting out, coming back from a setback, or looking to take your training to the next level, the team here meets you exactly where you’re at. The culture is welcoming, the programming is intentional, and the results are real.

I can’t recommend The Strength Den enough. It’s more than a gym — it’s a place where people get stronger, the right way.

- Alex Nuccio, Mill Valley

"I’ve been working with Denzel for 3 months to try to regain strength after two major back surgeries a few years ago. Because my back has a lot of metal holding it together it is completely inflexible. While protecting my back I’ve let the rest of my body become very de-conditioned.
Denzel has done more to help in 3 months than 10 yrs of PT, chiropractors, water aerobics, exercise classes, acupuncture, chronic pain management groups, walking and on and on. He is slowly and competently building my body back up. He pays close attention to my movements and sometimes by tiny adjustments relieves whatever pain I’m having from the position. I never believed I’d be able to move so freely again. I’m already much stronger. I look forward to my M-W-F workouts all week. I finally have HOPE that I’ll be able to return to some of the activities I’ve abandoned along the way due to pain and weakness."

- Ginny Walters, Mill Valley

"I've gone to semi-private workouts at Strength Den for a year and cannot recommend the program highly enough. Denzel has built a customized training plan for me, focused on total body strength and mobility all geared towards getting me back to competing at former D1 level in golf now in my mid-30s. Not only have I seen amazing improvement in speed and stamina on the course, but have completely gotten rid of nagging shoulder and back injuries and am more confident applying my new strength to any athletic pursuit. Even my day-to-day body positioning and awareness has improved.

The gym itself is the perfect setup to focus and improve each week. Denzel changes my workout frequently to keep pushing my limits, and is amazing at refining basic techniques I've done for many years with other coaches (bench press, squats, etc) as well as slowly incorporating news ones that are on the cutting edge of my sport's fitness training, consistent with what I've seen the top pro athletes doing. The available times are perfect to suit my schedule, and whether I book a session in the morning or night and whether I'm alone or with a couple of other people I get a ton out of each session physically and mentally with his constant coaching and feedback."

- Alex Bon, Mill Valley

Looking for highly skilled personal training in a small group setting? Over going to large group fitness classes that don't address chronic injuries etc? Want to get the fittest ever for that skiing, running or just carrying all those Amazon packages up the stairs? Strength Den has entered the chat. Owner Denzel has created a genuinely community-oriented environment coupled with highly personalized programming for each client. Coaches Mike and Surbhi are excellent at being supportive and motivational and inventive with your circuits depending on your needs. I looked for something like this for several years and am now a total fangirl of functional strength training at the Den!

- Rebecca Rothberg, Mill Valley

I am an older adult, And wanted to get stronger and feel more confident in my daily activities. Denzel and his staff helped me to achieve my goals. Their caring expertise guided me at every workout. This has been an amazing experience with truly wonderful, caring people. I can’t recommend this place highly enough.

- Karen Goldberg, Mill Valley

Want abs in 3 weeks!? Join Strength Den!! No seriously, since joining the den I've noticed an immediate difference in my body and my strength. One of the things I love about a strength den workout is it's not a HIIT class, it's not about sweating as much as possible or feeling exhausted when you leave. It's about doing what's right for your body, getting stronger, and focusing on correct positioning. Along the way you happen to get fit and feel great, sounds like a great symptom to me! Not to mention the people are wonderful and you start to develop a strength den family when you work out there.

- Sasha Nuccio, Mill Valley

I've been going to weekly individually-tailored workouts for a year now, and I've never felt better physically. Strength Den has become the perfect compliment for my passions of surfing/biking/trail-running, especially since I've rounded the 40-year mark and am more susceptible to falling out of alignment and/or sustaining injuries. Strength Den's philosophy is not about getting jacked (like many other gyms), but rather about developing functional fitness, customized for your specific sports and physical goals. Many of the muscles that I've been training are the often neglected ones that you don't see in the mirror, but they are often critical to optimal performance and injury avoidance. I never thought I'd be the type who goes to a gym, but this is not a normal gym, and now I can't imagine going without it! Thank you Team Strength Den!

- Dave Schlachter, Mill Valley

"Denzel is a magician! I came in wanting to get stronger and more toned, without getting buffed and bulky, and I have achieved so much more than that! I am stronger now than I ever imagined I could be and have beaten two injuries - one from running, the other from skiing. And he whipped my posture and balance into shape while he was at it. Best investment I have ever made."

- Claire Conway, Mill Valley

Denzel Allen's breadth of knowledge and brilliant approach are nonpareil, and I am exceptionally grateful to be working with and learning from him, and getting stronger thanks to his expertise.

After 25 years of casual marathoning, strength training, boot camping, mountain biking, TRXing, and engaging in myriad forms of exercise (with a lot of hubristic poor-forming along the way) I've recently suffered a raft of serial injuries that took most fitness modalities off the menu. Yeah. Crummy.

Enter Denzel and The Strength Den.

I first began working with Denzel shortly after being diagnosed with a torn disc in my lower back. He crafted a personalized training plan for me, and with his guidance I have not only been able to continue to maintain strength as I recover from my injury, but I have also been able to build more strength in the process—by learning *truly* proper form and by unlearning, with his nuanced guidance, patterning that has likely exacerbated/led to my injuries. He's constantly changing up the workouts and is always deeply attuned to my strengths and limitations, which vary from day to day, and I appreciate his stalwart commitment to keeping my form on point.

Denzel's super personalized attention, rooted in his wisdom and experience that says anybody can build and maintain strength—and every single body is different—is particularly important for me not only as a person negotiating injury but also as a fifty-year-old woman. I'm not interested in "killing it" or "crushing it" at the gym or in faddish workouts or vapid health club scenes. What I'm interested in is staying strong, and staying strong smart—for life.

Lucky for me, that's precisely what Denzel is helping me to do—and what you, too, will find in the Strength Den community!

- Kris Grossman, Mill Valley