There are 4 categories of Exercise; stretching, aerobic exercise, strength training and functional training. And I am talking about Strength exercise here.
I believe, Strength exercise is the most important exercise among T2DM population. Because of insulin resistance in muscles.
When we have less muscle mass, we don't have enough sensor that detect glucose in blood stream. So that we must build muscles mass and have more sensors.
Another reason we need more muscle mass. Muscle is for storage for energy. More muscle = more storage. Physical activity and exercise will increase glucose metabolism.
We will be able to put glucose as energy (glycogen) in the muscles, and use as fuel for activity (metabolism) instead of stored as body fat or remain in blood stream.
Increase muscle mass are associated with improve glucose regulation.(Fiore) Every 10% increase in the ratio of skeletal muscle mass to total body weight was associated with an 11% reduction in risk of insulin resistance and 12% drop in risk of transitional, prediabetes, or overt diabetes (Srikanthan, P).
I would recommend to lift weight. Find the weight range that you be able to perform 6~8 repetition easy. and do 4~6 sets.
If you are the beginner, I would recommend to have someone who could check your form well Life weight without compensate movement. this prevent injury and exercise will be more effective. Start with smaller weight, less repetition, and sets.
Do 4 times per week. However, this will be too much frequency of training for T2DM individuals. If you never lift weight or if you have not life weight little while, I recommend to start slow pace, and progress the weight, repetition, sets, rest time and frequency slowly.
Always, listen to your body. If you feel tired stop what are you doing. If you have pain, don't push through. Stop right way. This way we prevent fitness injury and keep exercise long term. Thus, you get results!
Please don't forget to check your blood sugar before exercise, if your blood sugar is >100 mg/dl eat Carbo Wait to do exercise if your blood sugar is over 250 mg/dl take medication and manage blood sugar.