Featuring Cybex, Hammer Strength and Life Fitness equipment…we have several options to meet your lifting needs. Squat and heavy lifting racks, pull up bars, leg and chest presses, benches, adjustable pulley systems and much more.

Our weight rooms are divided into two spacious sections with lower body on one side and upper body equipment and free weights on the other. Our dumbbells go all the way up to 60pounds. During peak after work hours, you can usually find someone to spot you. Come get your lift on at AFNS.


Looking for motivation or working out with a specific goal in mind? Members may purchase one on one sessions for personal training with one of our certified trainers.

Our trainers can help you ditch a sedentary lifestyle, build muscle and strength, lose weight, become more agile and flexible or recover from an injury. You can view trainer bios in the club.

Call or stop in and submit a trainer request form at our front desk, and a trainer will get back to you to discuss your options.
Rates: 1 session $90, 10 sessions $850, 20 sessions $1600

Before purchasing PT sessions, please stop by our front desk and grab a trainer request form. Complete and return this form at the front desk and one of our trainers will call you to discuss your options. Members may purchase sessions in person at the club or online by using their membership # as both username and password via

Meet Our Personal Trainers


Jake began CrossFit in 2008 as a strength and conditioning program for volleyball and quickly fell in love with it. He continued pursuing it throughout his collegiate volleyball career, got his level 1 certificate in 2014, and began coaching in 2015. Jake quickly discovered a passion for coaching and obtained his level 2 certificate just a few years later in 2017. 
Given his background with CrossFit as it relates to sport, he is always eager to chat about how the things we do in the gym can be applied to our favorite game, sport, or just life in general. Whether it’s kicking into a handstand, hitting that weightlifting goal, or even just picking yourself up off the ground, Jake loves helping people achieve things they never thought their body would be capable of doing and wants to help you build a healthy, long-lasting relationship with movement and fitness.


Jill has had a lifelong love of fitness, and realized the importance of strength training and mobility while playing Division I field hockey. She started CrossFit in 2015 after practicing yoga for 10+ years and finding it wasn’t giving her the same results. One of her yoga instructors was also a CrossFit coach and suggested she give it a try. She hasn’t looked back since, having fallen in love with the results and how strong it makes her feel. 
Jill got her Level 1 coaching certificate in 2019 and started coaching in 2021 due to the pandemic. She loves the friendly, welcoming community at CrossFit Mariner Square. Jill also leads a 30 minute stretching and mobility class here every Wednesday at 6p called Stretch It Out. This free class is a great way to check out her instruction and to become more limber. Jill incorporates both mobility and technique into her coaching style, and is passionate about helping people of all ages and capabilities feel strong in their workouts and their everyday life.


While not a gifted athlete at a young age, that didn’t stop Don’s desire to be the best he could be and participate in as many sports as he could. Skiing, Baseball, Basketball, Football, Track and Field were all part of his early childhood experience.  Swimming became the main focus from High School to College. Don competed locally for Hayward High and his freshman year at Chabot Jr. College. He transferred to CSU Chico where his competitive swimming career came to an end. Through his high school and college years Don taught swim lessons to all age groups.  He was the head coach for a summer swim team in San Leandro and an assistant coach for a local USA swim team.


Don has maintained his fitness routines over the years and after ending a career in the insurance business, he is now available to guide you with your fitness goals. Don holds a degree in Kinesiology from Cal State University Hayward/East Bay. Customizing a fitness program that fits your needs is what Don can do best for you. Whether you need a basic fitness routine or you want to train for a triathlon, 5k, 10k, ½ or full marathon, Don can provide you with the training techniques for you to meet your goals. He believes that to achieve the best fitness results all you have to do is have fun, be consistent, adapt to body changes, and focus on the journey-not the destination.


Sharon found CrossFit after years of running had taken its toll on her knees. Her doctor recommended easing the damage by lifting weights instead of something so high impact. A friend suggested CrossFit and it was love at first power clean. Mother of two, CrossFitting since 2012 and a CF L-1 trainer since 2016, Sharon offers a variety of workouts, using weight training to help you break through plateaus and achieve your personal best. She possesses the right combination of patience, knowledge, and motivation that you’d expect from a good trainer.
Sharon works with people of all skill levels, but is especially motivating for those who are looking to kick it up a notch. Sharon believes you can do anything you set your mind to and will prove that philosophy one session at a time. If you are looking to get stronger, leaner and to have more energy and stamina, Sharon is the trainer for you. 


Stefanie has been a personal trainer since 2002, and a Pilates teacher starting in 2004 with Matwork and continuing in 2009 for apparatus, mainly Reformer. Stefanie currently teaches our Pilates Apparatus classes and offers Private lessons as well. Stefanie is ACE (American Council of Exercise) certified for fitness and both PhysicalMind Institute and Balanced Body for Pilates.

Stefanie favors a rounded, multidisciplinary approach to training focusing on posture and alignment, good form and technique, and a strong active core. Her goal is to educate and guide, helping clients to achieve their fitness goals.She brings an educated eye and an understanding of the process we all go through as we reach for a healthier lifestyle. Stefanie has been described as “gentle, but tough”. Two severe injuries in her youth put Stefanie on the path to fitness and she has never strayed far from it. Stefanie started with martial arts and yoga, then became a dancer for most of her life, and continues on with strength training, Tai Chi and Pilates.

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