
Some of the nervous system side effects that may be caused by cancer or cancer treatment include the following:
• hearing loss and/or tinnitus (ringing in the ears)
• vision loss and/or vision side effects (such as blurred or double vision)
• speech difficulties, such as slurred speech, difficulty expressing oneself or understanding speech
• cognitive (thought process) changes including decreased memory, problem-solving, and calculation
• changes in taste and smell
• difficulty swallowing
• problems with balance, dizziness, vertigo (feeling like the room is spinning), and nausea
• ataxia (problems with coordination) and movement, including problems with posture, walking or holding objects
• asthenia, a general weakness that causes an overall lack of strength; hemiparesis (weakness on one side of the body); drowsiness
• paralysis of different parts of the body, ranging from hemiplegia (paralysis of one side of the body) to paralysis of a smaller area, such as the muscles in the face
• seizures
• changes in the functioning of organs, which can cause constipation, incontinence (inability to control the flow of urine), and impotence (an inability to get or maintain an erection)
• pain which can be caused by a tumor pressing on the nerves or damage to the nerves from treatment
• peripheral neuropathy which is a condition caused by damage or irritation to the peripheral nerves. The symptoms may include numbness, tingling (“pins and needles”), or burning pain in the arms, hands, legs, or feet; decreased ability to sense hot and cold; difficulty lifting the feet or toes; difficulty picking up small objects; decreased muscle strength; vision or hearing changes; and/or constipation
Nervous system side effects are caused by many factors, including cancer, cancer treatments, additional medications, or other disorders. The symptoms may appear soon after treatment or may appear several years after treatment.

Andrea Leonard graduated from the University of MD in 1990 and went on to get certified as a Corrective Exercise Specialist and Performance Enhancement Specialist by The National Academy of Sports Medicine (NASM). She has been certified as a personal trainer by The American College of Sports Medicine (ACSM), the National Academy of Sports Medicine (NASM), the American Council on Exercise (ACE), and as a Special Populations Expert by The Cooper Institute. She is also a continuing education provider for NSCA, NASM, ACE, and AFAA. Andrea is part of the Hedstrom Fitness/BOSU® Development team and the Chairperson for the Medical Fitness Network Advisory Board. She makes herself available as a volunteer mentor for other cancer patients through Immerman Angels.
Andrea is a 34-year year cancer survivor and has/had twenty one first-degree relatives diagnosed with cancer. In 2015 she lost her father, Morton, to complications of bladder and prostate cancer and myelodysplastic syndrome.
At the age of eighteen, Andrea was diagnosed with thyroid cancer and underwent a complete thyroidectomy and radioactive iodine treatment. It was through her own personal struggles that Andrea decided to become a personal trainer. She wanted to be able to help others, like herself, who struggled with the same issues of weight gain and poor self-esteem following cancer surgery and treatment.
Andrea began training in 1992 and worked at the National Capital YMCA in Washington, D.C. She quickly worked her way up to Director of Personal Training and ran the department for several years. While working at the YMCA, Andrea started Leading Edge Fitness and later, The Cancer Exercise Training Institute. While training the “movers and shakers” on Capitol Hill, Andrea’s mom was diagnosed, for the second time, with breast cancer. She watched her mother struggle through the trauma of multiple surgeries, reconstruction, a frozen shoulder, and addiction to narcotics in order to cope with the pain associated with her surgeries. Inspired by her mother, Andrea, along with a medical advisory board from Washington D.C.’s premier medical centers, set out to write “Essential Exercises for Breast Cancer Survivors.” The goal was to help the millions of men and women, like her mother, to gain back their strength, range of motion, and self-esteem (among other things), following breast cancer surgery and treatment. The book was published by Harvard Common Press in 2000.
Realizing that she is limited to helping a certain number of clients per week, Andrea developed the Cancer Exercise Specialist™ and Breast Cancer Recovery BOSU® Specialist™ Advanced Qualifications for health and fitness professionals. Through these programs she has been able to pass on her wealth of knowledge, and enable health and fitness professionals around the world, to work safely and confidently with cancer patients.
Andrea has presented the Cancer Exercise Specialist Workshop across the U.S. and Canada and has been a guest speaker at Medical Fitness Tour, IDEA World, CPTN Personal Trainer Summit, IRHSA, TSI Summit, Medical Fitness Association Conference, Keiser Permanente Thriving with Cancer Conference, Winona State University – Survivors Unite, McHenry Community College, New York Institute of Technology, OHSU School of Nursing, Edwards Hospital, Georgetown University Hospital, Suburban/Johns’ Hopkins, Mennonite Cancer Foundation, South Georgia Medical Center, Cary Medical Center Lynchburg General Hospital, Chesapeake Regional Medical Center, Sibley Hospital, Memorial Hermann, Sandford Health System, Avera McKennan Prairie Cancer Center, Baptist Hospital East, Patricia Neal Rehab. Center, St. Mary’s, Baptist Health System, and Fort Bliss Army Installation.
Andrea has written 14 books on the subject of cancer and exercise and has contributed to PFP Magazine, NOU Magazine, US News and World Report, Club Solutions Magazine, Bethesda Today, Capital Gazette, NASM’s Training Edge Magazine, Lake Oswego Review, Portland Tribune, The Oregonian, The Tidings inHealthOhio Blog and News, Capital Style, The Examiner, The Washington Post, Dallas Morning News, 4Wholeness.com, SpecialFit, and has appeared in countless videos including the Heartflex Breast Cancer Recovery video and been a regular fitness expert on AMNW.