About Keri

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Hi, I'm Keri! I'm a married mom of 3 boys. My twins, Drew (L) and Michael (R) are 13 yrs. (7th grade), CJ is 6 (1st grade) and is everything you'd expect in a little brother! These boys keep us busy!

My husband, Ed, is a health teacher and Head Football Coach for Boston College High School.

Our lives happily revolve around football, hockey, and lacrosse. As former athletes (my husband played football in college and I played basketball) we know the importance and value of sports for staying active, healthy, instilling teamwork and learning life lessons. Our weekends are full of games and practices and lots of travel, but we love it.

Like many of my clients, I understand the juggling act of work, family, and self-care. I'm here to make fitness and nutrition simpler for busy women, helping them achieve consistent results without unnecessary stress.

With With years of experience in fitness and nutrition, I'm dedicated to helping women like you feel their best....without losing their minds!


Keri's Education & Experience


Master's in Applied Exercise Science with a concentration in Strength and Conditioning - Springfield College - 2002

Bachelor's in Exercise Science with a concentration in Human Performance and Fitness - UMass Boston - 2000


Certified Macro Nutrition Coach - 2022

Certified Health Mindset Coach 2021

StrongFirst Bodyweight Instructor (SFB) May 2016

StrongFirst Level 1 Kettlebell Instructor (SFG) August 2015

Functional Movement Systems (FMS) - May 2015

Original Strength - April 2015

Metabolic Effect Hormonal Fat Loss Nutrition Consultant - 2014

Certified Strength and Conditioning Specialist - National Academy of Sports Medicine - 2002



Balance Body University - Pilates Reformer, Mat and Barre - 2010

Continuing Education: 

3 Pillars Method Nutrition Masterclass for coaches - 2023

Empowered Performance - 2020 + 2023

Pelvic Pro - 2021


Strength Coach - Mike Boyle Strength and Conditioning - 1999-2003

Director of Personal Training - Master Trainer - Fitness Unlimited - 2003 -  2010

Owner - Keri Mantie Personal Training - 2011 - Present


Boston University Strength and Conditioning - Fall 1999

University of Tulsa Strength and Conditioning - Summer 2001

The College of the Holy Cross Strength and Conditioning - Spring 2002