iTrainSoftball exists to develop complete softball players through high-end focused instruction, intentional training, and a deep understanding of how athletes truly improve over time. Our mission is to enhance softball skills development by building stronger, smarter, and more explosive players through professional-level teaching, body movement development, and skill mastery in a focused one-on-one environment. We emphasize the why behind every movement so athletes gain the awareness and discipline required to excel in youth softball training and perform at the highest level. Through relentless attention to detail and a commitment to long-term development, iTrainSoftball helps athletes unlock their potential and build the foundation needed to succeed in softball and beyond.

As a former program owner with more than 15 years of experience, an active player-development instructor working with athletes from youth levels through those now competing professionally, and a two-time honoree of the Boston Red Sox Foundation for on-field coaching excellence, John has helped develop thousands of athletes. He now brings that same next-level training and expertise to the softball world.
Beyond the wins, John is most proud of Kings for Kids, the charitable arm he created with his Triple Crown players. Inspired by essays his athletes wrote about wanting to help their communities, the program has partnered with Boston Children’s Hospital and seven local food banks, raising more than $30,000.
John’s approach remains hands-on and player-centered: a clear training structure, competitive pathway, and coaching philosophy that develops young athletes both on and off the field. While growth has brought the familiar challenges of any expanding organization—especially the need for dedicated training space and fields—he credits hard work, resilience, and focus rather than luck for the journey so far. His goal is simple and ambitious: continue building impact players and give them the kind of meaningful athletic experience that first inspired him to coach.
For more information on John, or connect with him on his baseball training got to his website:

At ENL, we are dedicated to creating a high-energy, positive, and supportive community where athletes of all levels can achieve and exceed their personal goals. We specialize in player development for baseball and softball through private instruction, camps, and clinics designed to enhance performance. Additionally, we offer strength and conditioning programs for athletes across all sports, as well as fitness training tailored to meet the goals of adults.

Professional Personal Trainer: NABF, Member NSCA, USAW Sports Performance Professional Softball Instructor: Hitting, Catching
Softball Background:-Merrimack College Softball Program 2003: 2 NCAA D2 Northeast10 Conference Championships, 1 NCAA D2 Regional Championship, and 1 Trip NCAA D2 College World Series -Dighton Rehoboth HS 1999 SCC All-Star 1996, 1997, 1998, 1999
Coaching:-Coyle Cassidy Head Coach 2015-17 -Taunton High School Assistant Varsity Coach 2007-2008 1 State Championship -Taunton High School Junior Varsity Coach 2006 -Wheaton College Softball Assistant Coach 2004, 2005 Catching Coach
Sports Performance: -Energy No Limit: Owner, creator, sports performance coach, and Softball instructor 2013, 2014, 2015, 2016, 2017 -Wheaton College Basketball: Conditioning Coach 2013, 2014, 2015, 2016, 2017 -Fielders Choice: Head Fitness Instructor and Program Director 2010, 2011 -Catz Performance Facility: Sports Performance Coach 2008, 2010, 2011, 2012

MSA, athletes benefit from hands-on coaching every step of the way. With a coach-to-athlete ratio you won’t find in bigger facilities, each athlete receives personalized attention to refine technique, improve form, and progress effectively.
From dynamic warm-ups to strength training, we guide each group every step of the way, creating a focused, supportive environment where athletes can improve safely and effectively.
Beyond sports performance, our program teaches athletes how to strength train properly - a lifelong skill that benefits them far beyond their playing field.
For more information, please email us at keri.mantie@gmail.com or emantie@bchigh.edu
Be sure to follow us on Instagram at @mantiestrengthacademy

Keri has spent her entire career in the fitness industry. She has interned as a collegiate strength coach at Boston University, Springfield College, the University of Tulsa, the College of the Holy Cross and is a Certified Strength and Conditioning Specialist.
After earning her Master’s degree in Strength and Conditioning from Springfield College, she worked as a strength coach at Mike Boyle Strength and Conditioning before transitioning to personal training and eventually launching Keri Mantie Coaching.
For more info go to https://kerimantie.com/about-me/

Ed is a former D1 athlete who worked as a strength coach at Mike Boyle Strength and Conditioning and spent several years as the Head Strength and Conditioning Coach for UMASS Lowell hockey before transitioning into teaching and coaching.
For the past 18 years, he has been a physical education and wellness teacher while also serving as a head football coach at Weston, Framingham, and Boston College High School, where he currently teaches health and wellness. He later moved to the collegiate level, coaching at Curry College.
For more info go to https://kerimantie.com/about-me/

Next Level is a soccer development company focused on private training, small group sessions , clinics and programs . Their mission is to help young players build strong technical fundamentals in a structured , supportive and high-level training environment.
Through consistent and target sessions, athletes receive individual attention to improve control , confidence and game understanding preparing them for long term development and success on the field.
For 1:1 or group instruction, Next Level can be reached directly at
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All rentals operate on a "rent at your own risk" basis. Staff may not be present on-site during these hours. Renters assume full responsibility for any personal injury, property damage, or loss that occurs during the rental period. The Renter assumes all responsibility for injuries, damages, or losses that occur during the rental period. The Renter agrees to indemnify and hold harmless On Base Performance, LLC, its owners, employees, and agents from any claims arising from use of the Facility. The Facility is not responsible for lost, stolen, or damaged personal property.
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