Team & Affiliates


Mark “Coach Rozy” Roozen started Coach Rozy Performance in 2014 when he came back to South Dakota, after working with the Cleveland Browns in the NFL.  He has been a Strength & Conditioning Coach with the NFL and College programs as well as work with all levels of athletes from grade school to Olympians. He was Certification Director for the National Strength and Conditioning Association (NSCA).

Coach is the President and Owner of Coach Rozy LLC, his company that handles public appearances and speaking, consultant work, performance training and offering performance products.

He is also Co-Founder of LIVE PAIN FREE – The Right Moves, which helps folks move right and exercise right to eliminate pain and movement problems in work, life and play.

Coach Rozy is also part of of 911 Tactical Performance, an organization that does consulting, education and training with police, firefighters and military groups throughout the country.

His training methodologies have been successfully applied to the full spectrum of the population youth, geriatric, rehabilitation, and a wide range of athletes.

Carlos “Coach Los” Sanchez, CSCS, CPT is  originally from Carson, California.  Carlos moved to Sioux City, Iowa at the age of 9.  He  was working at a family business running a restaurant and bar when he met Coach Rozy. Since that time he has shifted to a career in Strength and conditioning/fitness.  He joined Coach Rozy Performance the summer of 2020, working with teams at every level.  In 2022 Carlos took over the position of Assistant Director and Head of Program Development with Coach Rozy Performance.  Coach Sanchez enjoys working with all athletes and helping people get better and achieve their personal goals. His personal goal is to keep working on becoming a better coach while learning and gaining more  experience in the strength and conditioning field.

Carlos holds a Bachelors degree in Business Administration, is a Certified Strength and Conditioning Specialist (CSCS)-NSCA and a Certified Personal Trainer (CPT)- NASM.

As Carlos describes, “I just love watching young athletes get better and learn that through hard work and consistency all goals are obtainable.To get them to set the bar higher and continue to work to keep pushing to new levels is exciting.  When you can see them evolving into a better version of themselves – that’s what gets my juices going!”.

Miles Rademaker has been with Coach Rozy Performance, first as an intern from the University of South Dakota (USD).  After his internship, Miles started with Coach Rozy Performance in 2020.  A graduate of Lake Preston High School in SD, where he as selected Lifter of the Year 2x and was a 4x letter winner in football and track, Miles received his Bachelors of Science in Kinesiology and Sports Management and a minor in Psychology, from USD.As well as working with Coach Rozy Performance, Miles also works at AVERA Wellness Center as a trainer and coach.  “Building relationships with kids, and those I train – getting to see them grow and display their growth on the filed/court, or in the gym, is where I get my enjoyment and passion for working with Coach Rozy Performance.  Also, I love the chance to help develop a love for training and fitness we get to build with the folks I’m around that they can use for the rest of their lives” Miles shared.

Ronette Karstens has been with the Coach Rozy Team since 2015. She graduated from the University of South Dakota with her Bachelors Degree in Education.  She is currently a First Grade Teacher at the Gayville-Volin School District where she is Assistant Boys Basketball Coach as well as Assistant Track & Field Coach working with the jumpers.  With Coach Rozy Performance, Coach Ronette does performance training, leads Group Bootcamps and is Coach Rozy’s Personal Assistant, helping oversee business operations and office management.

Ronette truly “did it all” while at Gayville-Volin High School; participating in Oral Interpretation, Flags, Cheerleading, Band, Choir, the School Newspaper, Yearbook, Softball and Student Council.  She was named Salutatorian her senior year.  As an athlete she was awarded the Raider Award (for best athlete) and Academic All-State.

Ronette was a star basketball and track athlete starting on the varsity team as an eighth grader.  She was awarded most improved that year by her coach.  She earned team MVP every year after that as a freshman, sophomore, junior and senior.  her senior season she averages 13.4 points, 10 rebounds, five steals and 5 assists per game.   She still holds schools records in the high jump and triple jump.  With her past experience, knowledge and drive, she loves to work hard, focus and bring high energy to at all she does – helps her excel with the Coach Rozy Team.

Ronette has a husband, Justin who also coaches and is a part time assistant with the Coach Rozy Team. She has 3 boys, Caid, Spencer and Preston, whom she loves to spend time with and is involved with their athletic and school programs.

Justin Karstens, married to Coach Rozy Performance Coach Ronette Karstens, has been with the performance program since 2017.  Teaching and Coaching boys and girls his whole career, Justin brings a wealth of knowledge and sports skill to the Coach Rozy Program.

Justin, who is a High School Principal as well as a Coach, has been at Gayville-Volin for the past 14 years, where he has also been Heads Boys Basketball Coach for the past 8 years (he was previously Girls Head Coach at GV before that) and has been an Assistant Football Coach for the last 8 years.

As mentioned, Justin’s wife Ronette also coaches and is an assistant with the Coach Rozy Team. They have 3 boys, Caid, who plays baseball at Mt. Marty College, Spencer and Preston, who are heavily involved with their athletic and school programs at Gayville-Volin School.

Austin Miller graduated from South Dakota State University where he majored in Health, Physical Education, and Recreation. During that time, he worked with the men’s basketball team as a student assistant (2007-2013) and did his internship with the SDSU Strength and Conditioning staff (2010-213).   Austin has been with Coach Rozy Performance since 2019.  He also works as a player development coach, training basketball athletes from the youth to professional levels.
Toby Gall, CPT (NASM) –  is a graduate of Yankton High School and received his Bachelors of Science in Kinesiology & Exercise Science from the University of South Dakota (USD).  He joined the Coach Rozy Performance Team in the summer of 2022.

Toby has been around fitness for some time, working as a personal trainer and working in the gym setting for a number of years as well as being around the golf course working at the local country club.

Toby gets fired up when training and shares, “I love seeing the progress in athletes of all ages.  Watching them become bigger, faster, stronger is just great.  It’s great when they see the benefits and realize their potential.  It’s awesome seeing them excited about working out and getting to the gym.  Their excitement excites me”!

Halle Tvedt, is orginally from Highmore Harrold High School.  She is currently at student at the University of South Dakota in Vermillion, South Dakota.   Halle has been invovled and aournd sports, strength and conditioning programs her whole life and has fallen in love with sports and the profession of improving performance.  Halle says, “I love the physical and mental challegne that sports bring to young children, and the lessons can be used in every aspect of life”.

At USD, Halle is going ito a section of rehab services with the goal of helping folks that she works wherever and whenever she can.
Zoe Mojaver is from Houston Texas and is currently attending Graduate School at Mount Marty University for her Masters in Education and Coaching Leadership. She is also a Graduate assistant Strength and Conditioning coach at the University.    She has a Bachelors degree in Health Sciences and is a Certified Strength and Conditioning Specialist (CSCS)-NSCA. Something she loves about coaching is being able to contribute to the success of others. “Being able to build relationships with the athletes and be in an environment that encourages continuous learning helps me grow as a coach everyday.”

Ella Wragge is from Crofton, Nebraska. She is going to Morningside University in Sioux City, IA and studying political science. She is also on the  women’s basketball team at Morningside.  Ella is excited to be with Coach Rozy Performance, “I’m thrilled to be able to help out with training, as athletics have been a part of my life for as long as I can remember!”
Emma Christensen is from Yankton, SD and currently a junior at the University of South Dakota, in Vermillion, SD,  studying Kinesiology and Sports Management with a focus in Exercise Science! Emma has a long term goal of becoming a physical therapist and is working towards that goal.  Emma brings her excitement and expereince to Coach Rozy Performance.  Emma states, “I’m so excited to be given the opportunity to work with all the kids this summer! I loved the program growing up and can’t wait to give back and make it just as beneficial and fun as my coaches did for me!”
Jayden Horrach is from Colfax, Iowa and went to Colfax-Mingo High School. He attends Mount Marty University in Yankton, SD.  Jayden is pursuing a degree in exercise science.  He also is a memeber of the MMU football team playing in the offensive backfield with the team.  Jayden acknowledge, “I’m excited to get to help the kids in the Coach Rozy Performance program get better at their sport and see how far they can progress.”

Trevor Woods, MA, ATC, a high school graduate of Bon Homme High School in South Dakota, Trevor has a bachelors degree in Athletic Training from South Dakota State University (SDSU) and a Masters Degree in Exercise Science from University of South Dakota (USD). He has been providing Athletic Training coverage to Yankton High School and Gayville-Volin High School since 2002, ran AVERA’s Accleration Program for 13 years before joining the Coach Rozy Performance team in 2014.  

He continues to enjoy working with athletics both as a trainer and a performance coach, as he explains, “I really enjoy meeting new athletes and trying to make them the best they can be – and keep them healthy to maintain high levels of performance.  I have a passion to teach proper movement to help reduce risk of injury in all the kids we work with”.

Sarah Rockne, ATC started working with Coach Rozy Performance in 2019 as both a performance coach and as an athletic trainer.  A graduate of Yankton High School, Sarah went to South Dakota State University (SDSU) as well as Capella University to get her Bachelors in Athletic Training and her Masters in Sport Psychology.  

During the school year, Sarah helps to take care of a number of schools associated with Coach Rozy Performance and AVERA Sports Yankton.  Sarah says, “I enjoy being a performance coach with Coach Rozy Performance because we get the opportunity to teach athletes proper movement patterns and strength training that will carry over into their performance on the field, court, mat, etc.  Seeing the athletes working hard and improving week by week makes me pumped to se it all pay off for them!”.

Sarah Shippy, MA, LAT, ATC, is a high school graduate of Colome High School in South Dakota, Sarah continued her education at the University of South Dakota (USD) and the University of Nebraska – Omaha to obtain her Bachelor of Science in Kinesiology and Sport Management and her Masters of Arts in Athletic Training.  

Joining the Coach Rozy Performance Team in the Summer of 2022, and becoming athletic trainer to the MMU Football team in 2021, Sarah uses her knowledge she picked up while doing her internship at Syracuse University of the football team there and also working with the Omaha Lances USHL team.

“I enjoy being able to help athletes of all ages excel in their physical and athletic performance in a safe and team oriented environment” Sarah shared with Coach Rozy Performance.

Kevin O’Brien is a Physical Therapist in Yankton, SD with AVERA Scared Heart Hosptial.   He works with Coach Rozy Performance and AVERA Sports Yankton.  Kevin has specific training and skill in reducing patient pain and increasing mobility lost due to injury or illness. As a Physical Therapist, Kevin performs exercise therapy, endurance exercises, and pain and mobility assessments to help keep Coach Rozy athletes and members at their peak level of performance. If a need for Physical Therapy comes ups, having a team to help with total training and performance is key – and Kevin O’Briend and the team of Physical Therapist at AVERA Scared Heart are some of the best.

Jonah Miyazawa – Performance Coach 

Jonah started with Coach Rozy Performance in the summer of 2022.  From Hawaii, Jonah went to Iolani High School on the Islands and found his way to South Dakota through Mount Marty University.  At MMU he is working on his Business Degree and plays on MMU’s football team. His first year with the team, he earned GPAC honors as one of the top receivers in the conference.

His desire to work with Coach Rozy Performance comes from, as he says, “I have a passion to work with awesome people that share the same passion in building up and training the next generation”.

Jaren Mortensen – Performance Coach

A student at Duelesne High School in the state of Utah,  Jaren is now a student and on the football team at Mount Marty University.  Jaren join Coach Rozy in the summer of 2022.

Jaren explains why he wanted to join the Coach Rozy team, “I enjoy coaching the kids that are involved in Coach Rozy’s program.  It’s awesome to see them get better throughout working with them on a day to day basis.  It also is great to see as an athlete that is coaching how hard work, dedication and “showing up” each day really does separate the good from the great”.


911 Tactical Performance

Live Pain Free – THE RIGHT MOVES

Jeffrey Paul Salon


Performance Sandbag Training

Performance Sandbag Training