Type 2 diabetes is a disease that affects millions of people worldwide and is on a continuous increase. It occurs when the body’s cells become resistant to the hormone insulin, causing a compensatory increase in the insulin hormone (insulin resistance) and overtime leading to high blood sugar levels. Insulin resistance itself is a health condition and a precursor to type 2 diabetes. The largest risk factors are poor physical exercise and poor nutrition.
The best type of exercise for someone with type 2 diabetes and/or insulin resistance:
Exercise is a front-line treatment for the prevention and management of type 2 diabetes and insulin resistance. High-intensity resistance exercise and high-intensity cardio exercise have both been shown by science to be safe and particularly effective for improving insulin sensitivity, glucose control, beta-cell function and abdominal fat loss compared to other forms of exercise in people living with type 2 diabetes [1-8].
Resistance exercise, also known as weightlifting, involves using external resistance (such as weights or resistance bands) to load and stimulate the muscle system. High-intensity cardio exercise also known as high intensity interval training involves short bursts of high intensity bouts interspersed with periods of lower intensity or complete rest. High-intensity exercise in forms of resistance or cardio requires less time commitment, making it very beneficial from both a time management & physiological standpoint.
The potent benefits:
It is important to understand that skeletal muscle is one of the largest organs in the human body. Muscle releases hormones known as myokines, which have beneficial effects on glucose control, insulin sensitivity and the function of other organs like the pancreas and the brain [9-12]. This makes resistance training a very important medicine, not just for glucose control, but for overall health.
Muscle is the largest depot for glucose and carbohydrate. 80% of the carbohydrate we eat goes into our muscle tissue to be stored or used. If our muscles are already full, the carbohydrate we eat will likely be stored as fat and/or will leave a diabetic with high blood glucose levels.
High-intensity exercise in the forms of cardio or resistance exercise uses lots of glucose for fuel and once you complete a session, your muscle will have more room for blood glucose to move into therefore lowering blood glucose levels. In addition, due to reduced glucose in the muscle, your body will use more fat as fuel after the session is completed. These beneficial effects can occur after a single high-intensity exercise session and can last for 24-48 hours [13-15].
High intensity exercise also promotes large increases in certain myokines, glucose transporters, insulin receptors as well as improving mitochondria, and reducing inflammation which all assist in improved blood glucose control and insulin sensitivity.
Another important benefit which is amplified from resistance training is an increase in resting metabolic rate. Muscle is a metabolically active organ and uses lots of energy, even at rest. It is well-known that reduced muscle mass and/or poor muscle quality reduces resting metabolic rate. You may often hear people say that as they age their metabolism has slowed down and this is usually associated with reduced muscle quality/size which occurs with age or disuse. Increasing muscle quality is associated with a higher resting metabolic rate [16, 17] which is important for weight loss. An increase of muscle mass/quality will also allow for further improvements in blood glucose control.
High-intensity exercise in forms of cardio or resistance are shorter in duration and do not require large time commitments. Furthermore, a common belief when it comes to resistance training is that the weights need to be heavy. This is false and in fact, lighter weight with higher repetitions till a point of failure can result in similar outcomes as using heavy weight but with less stress on the joints. In addition, “high intensity” is dependent and relative to what the individual can do.
High-intensity exercise in the form of resistance or cardio are the optimal types of exercise for type 2 diabetes and insulin resistance. Combining high-intensity resistance exercise and high-intensity cardio exercise will yield added benefits. In addition, these exercise protocols in combination with a low carbohydrate/high protein diet can cause the reversal or remission of insulin resistance and type 2 diabetes. It is important to consult with an exercise physiologist who can prescribe you with a safe, effective, and individualised exercise program.
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