
Meet The Team
Our board-certified Registered Dietitians have the specialized training and experience to help you meet your individual goals
Founder & President
Cristina Rivera
MS, RD, CSSD, CDN, CEDS-C
Phone: 516-330-6040
Email: Cristina@longislandsportsnutrition.com
Cristina Rivera is the President and Founder of Nutrition in Motion, P.C. She holds a Bachelor of Science degree in Clinical Psychology and a Master of Science degree in Clinical Nutrition from New York University. She is currently licensed and credentialed as a Registered Dietitian (RD), New York State Certified Dietitian-Nutritionist (CDN), and holds board certifications in both sports nutrition and eating disorders treatment.

Cristina's Story
Cristina has over 15 years of experience working as a board-certified Specialist in Sports Dietetics (CSSD), the premier sports nutrition professional certification. She has worked in sports nutrition with athletes and teams at the high school, college, professional and Olympic levels. Cristina is also a Certified Eating Disorders Specialist and Consultant (CEDS-C) with extensive training and experience in the treatment of anorexia nervosa, bulimia nervosa, binge eating disorder, ARFID and other specified feeding or eating disorders. Having a combined expertise in sports nutrition and eating disorders, Cristina possesses a comprehensive and specific skill set to work within the overlap of athletes with eating disorders.
Cristina is an iaedp approved supervisor and provides peer case consultation and training to other healthcare professionals working in the fields of sports nutrition and eating disorders. Cristina has presented at symposiums, served as a member of peer reviewed panels and is available for speaking engagements and new opportunities.
Dietitian
Ashley Vadasz
MS, RDN, CDN
Phone: 516-330-6040
Email: Ashley@longislandsportsnutrition.com
Ashley Vadasz is a Registered Dietitian (RD) and New York State Certified Dietitian-Nutritionist (CDN) who earned her Bachelor of Science degree in nutrition and dietetics from Long Island University-Post. She completed her dietetic Internship with a focus in clinical nutrition, and her Master of Science degree in integrative and functional nutrition from Stony Brook University.

Ashley's Story
As a former three-sport athlete, a Marine Corps Veteran and an avid runner, Ashley has a personal passion for fueling for performance. Ashley has a diverse background working with CrossFit, high school- and collegiate-level athletes and special populations to include Veterans at the VA hospital in Northport, New York and firefighters at Brookhaven National Laboratory Department of Energy research facility. Ashley has experience with nutrition throughout the lifecycle to include areas of pediatrics to menopause.
When Ashley is not educating people how to nourish their bodies, she spends much of her time hiking and being active outdoors in nature with her son and dog.
Dietitian
Melissa Vasikauskas
RDN, CDN
Phone: 516-330-6040
Email: Melissa@longislandsportsnutrition.com
Melissa Vasikauskas is a Registered Dietitian Nutritionist who earned her Bachelor of
Science degree in nutrition at CUNY Brooklyn College. She completed her dietetic internship at Stony Brook University, where she gained extensive personal experience in many different settings, including inpatient and outpatient care, long-term care, diabetes education, and food service.

Melissa's Story
Melissa has been nutrition counseling for eight years and specializes in helping people break out of chronic dieting cycles by teaching them how to properly nourish their bodies. Melissa helps people learn how to trust their bodies and to develop confidence in the choices they make. Using an intuitive, non-diet approach that considers the psycho-social and emotional factors that influence food choices, Melissa's patients heal their relationships with food so that they can go on to live healthy, abundant lives.
Melissa is also the mother to a ten-year-old and understands how important it is to develop a healthy relationship with food—not only for oneself, but for future generations.
Dietitian
Josh Sisk
MS, RDN, CDN
Phone: 516-330-6040
Email: Josh@longislandsportsnutrition.com
Josh Sisk is a Registered Dietitian (RD) with a Master of Science in Dietetics from Marshall University and a Bachelor of Science from West Virginia University.

Josh's Story
Josh has extensive experience in sports nutrition, working with Division 1 football players at both Colorado University-Boulder and West Virginia University, as well as elite CrossFit athletes. He specializes in body composition, behavior change, and performance-fueling strategies.
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With a background in culinary arts, Josh also brings expertise in meal preparation, menu planning, and developing performance-focused recipes.