Owner/Head Coach Justin Ahrens

Owner, Founder and Head Coach of TreeLine CrossFit has been participating in the sport of CrossFit since 2010 and has been coaching the sport of CrossFit since 2012. He has qualified for five (2012/2013/2015/2016/2017) CrossFit Regional competitions and competed in four of them. He had his best placed finishes of 4th in the 2013 Asia Regionals, 7th in the 2015 Meridian Super Regionals, and 1st when he competed on the CrossFit Fort Vancouver Team in the 2017 West Regional and went on to place 3rd in the 2017 Reebok CrossFit Games Affiliate Cup. Justin has assisted in opening/managing multiple CrossFit affiliates in Dubai of the United Arab Emirates before relocating back to the beautiful state of Oregon where he coached at both CrossFit Fort Vancouver and CrossFit Pearl District. He and his wife, Cassie, decided home (Eugene) is where they were called to be and strived to open TreeLine CrossFit in 2017, to make as positive of an impact on the Eugene/Springfield community as they could. Let’s meet Coach J.

What is your favorite healthy meal and cheat meal?

  • My favorite healthy meal is: Grilled Chicken, Spinach/Kale, Avacado, Asparagus, Bell Peppers, Brussels Sprouts, Sweet Potato, and Goat Cheese.
  • My favorite cheat meal is: Pizza or A Fatty Burger and Sweet Potato Fries…oh and a Donut.

Are you a Duck or a Beaver?
Ducks 100%

What advice do you have for new members at TreeLine?
Take the process day by day. Be patient and trust the program. Don’t get frustrated, but instead use that frustration as motivation to better your life and way of living. Embrace the change that is occurring in your life and the community that is now surrounding you within TreeLine. Use this community for support and motivation. Show up every day and let us make this the best hour of your day. Work as hard as you can every time you step through our doors and make sure you walk out our doors with zero regrets. Eat clean, train dirty, make friends, and have fun. That last one is extremely important! We want this place to be a place you can call home and be your true self. We want you to WANT to come here and to be excited to workout here.  


  • Founder/Owner of TreeLine CrossFit
  • Head Coach
  • Level 1 CrossFit Certified
  • Level 2 CrossFit Certified
  • Carl Paoli Movement Seminar Attendee 

Professional Supporter and "The Wife" Cassie Ahrens

Cassie Ahrens is the backbone of TreeLine CrossFit. She has been married to Coach Justin for seven years, but has been by his side for eleven years. She herself is a very talented athlete. She has played all sports growing up, but continued to play Softball and Volleyball on scholarship in college. She currently is an elementary school teacher in Halsey, Oregon and has a way with kiddos that we all wish we had. She takes great pride in the self-confidence CrossFit has provided her and the things she has achieved because of it. Cassie makes a mean guacamole and is a strong believer in the fact that “Taco Tuesday” shouldn’t only be on Tuesday. She also would much rather watch Monday Night Football than almost anything else. 

What is your favorite healthy meal and cheat meal?

  • My favorite healthy meal is: Grilled Chicken, Avacado, Steamed Broccoli, Sweet Potato, Quinoa Brown Rice, Garlic and Goat Cheese.
  • My favorite cheat meal is...I have many.  A bowl(s) of Honey Bunches of Oats (the blue box), a big fatty burger and sweet potato fries, or a major cheat would be an Olive Garden date with Kaylee for soup, pasta, and tons of breadsticks.

Are you a Duck or a Beaver?
Go Ducks BABY!

What advice do you have for new members at TreeLine
My advice to new members is to never take yourself too seriously, find a workout buddy, and never go 2 weeks without doing squats.
Having fun is such a great, important part of working out and being healthy! We want TreeLine to be a place you WANT to come to, and we love to have fun, so don't be afraid to be silly with us!
Have not only a gym, class, or coach to hold you accountable, but having someone you can text when you need some motivation, make sure they're going to make it to class that day, or to make fun of yourself when you can't sit down properly on the toilet, workout buddies are great! Don't have one yet? Pick me!
Lastly, see above about not spacing your squats out too much. Nobody likes being stuck on the toilet.

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Coach Ben Stoneberg

Ben is well recognized name in the world of CrossFit and rightfully so. Ben has been to the CrossFit Games FIVE times and counting. He has qualified for 7 CrossFit Regional competitions. His experience in the sport is undeniable and is respected. He is from the Eugene/Springfield area, growing up in Coburg and attending Sheldon High School where he was voted "Most Athletic". Ben is just as experienced in coaching as he is in competing and is eager to help in anyway he can to help you move better and make TreeLine better. If you can't find Ben at TreeLine, your best bet is to look for him in the Costco Tire Shop.

What is your favorite healthy meal and cheat meal?

My favorite healthy meal would be smoked chicken, sweet potatoes, peppers, and eggs all scrambled up with avocado on top. 
My favorite cheat meal is pizza with a sour beer or dry cider. 

Are you a Duck or a Beaver?

What advice do you have for new members at Treeline? 

Come in with a positive attitude, knowing that you're coming to be a healthier you! Having fun is most important, and trusting the process will only make you better. You will have bad days and good days. The bad days are where you really grow as an athlete and person. Overcoming obstacles in life will make you only stronger. We are here to help make you healthier and hope this will truly be the "Best Hour of your Day". 


  • Level 1 CrossFit Certified

Coach Dennis Capel

Dennis has been a part of the TreeLine Family since before we opened our doors. He has been around athletics for his entire life, growing up playing football he was introduced to lifting at an early age. He found CrossFit not long ago and has been hooked ever since. He wishes he learned about it sooner. Dennis has made massive strides since joining the family and shows no signs of looking back. His full time job is a recruiter for the Army National Guard. 

What is your favorite healthy meal and cheat meal?

Healthy meal: chicken, veggies and rice/
Cheat meal: cheeseburger with sweet potato fries and a bowl of ranch.

Are you a Duck or a Beaver?

What advice do you have for new members at Treeline? 

My advice would be to "STICK WITH IT!" I know it can be overwhelming at first learning all of the movements and new people, but we are a family and everyone is here to help you out. We have all started from the bottom at some point.


  • Level 1 CrossFit Certified

Gym Mascot Griffey aka Griff

Griffey is our one and a half year old GoldenDoodle. He is still a pup. He is super friendly and loves everyone. Although he is super mouthy, we can assure you it is not an attempt to bite. He is simply showing his love by putting your wrist in his mouth. If you sit next to him, he is sure to lay in your lap and will make it difficult to get up and leave him. He loves to go on walks and/or runs, so no need to even ask about taking him for a walk...just do it. Although he may pull a little, don't let him. Feel free to bring him treats, we don't mind!  Show him all the love you want...HE DOESN'T SHED!