Aging is typically associated with a decrease in skeletal muscle mass and muscle function, which contributes decisively to disability in old age and to the loss of quality of life.Resistance exercise can increase muscle strength, function and mass in older adults.

The primary aim of this study is to determine whether the combination of resistance training with a supplementation of a cysteine- rich whey protein isolate (Immunocal) compared to combination of resistance training with casein used as control (casein contains little cysteine) could have the potential to provide a synergic beneficial impact on muscle mass and function which could translate to an improved quality of life in elderly persons.

Inclusion Criteria:

• Age 65 or older
• Estimated GFR above 45ml/min
• Total bilirubin in the normal range (0.2 to 1.2 mg/dl) AST (10-35 U/L for women and 10-50 U/L for men). ALT equal to or less than 2.5 times the upper limit of normal
• BMI between 18.5-29.9 (kg)/m2
• Sedentary (< 2 hours of structured exercise)in the last 2 or 3 months
• Based on investigator judgment according to current Canadian guidelines, medical conditions such as hypertension, diabetes and hyperlipidemia have to be stable and optimally controlled before the subject starts the study.

Exclusion Criteria:

• History of angioedema or allergic reactions to any compound used in this study.
• Milk protein intolerance
• Subjects currently using N-acetylcysteine, alpha-lipoic acid supplements, or dry whey protein supplements.
• Major surgery in the year prior to testing
• Acute coronary or vascular event within the last year or progressive angina
• Stroke within the past 2 years
• Neurologist and/or orthopedic limitations
• Uncontrolled thyroid or pituitary disease
• Medication which has a major affect on cognitive function
• Signs of early dementia as assessed by Mini-Mental State Examination
• Weight loss of more than 4kg(or more than 5% body weight) over last 6 months
• Alcohol abuse
• Medication which interferes with muscle mass i.e. (corticosteroids)
• Any life threatening conditions based on Investigator judgment.
• Subjects with allergies/intolerance to soya.
• Subjects currently undergoing immunosuppressive therapy.