Effort During Resistance Training in Type 2 Diabetes

Resistance exercise training can be both effective for the management of type 2 diabetes mellitus (T2DM) and appealing for individuals living with T2DM, and has been shown to be a viable exercise prescription option for this population. It has been suggested that the degree of effort is important for acute improvements in glucose metabolism and insulin sensitivity in individuals living with T2DM, although direct evidence of that is lacking. However, performing resistance exercise sets with a high degree of effort is associated with higher perceived exertion and discomfort, increased muscle soreness, negative perceptual responses, and higher neuromuscular fatigue and muscle damage. Taken together, these negative perceptual and physiological responses to resistance exercise sets performed with high degree of effort might negatively affect enjoyment, self-efficacy, and motivation during a resistance exercise session, ultimately reducing long-term adherence.

The primary aim of this study is to assess the effects resistance exercise training with different degrees of effort on glycemic control and psychological responses in individuals living with T2DM. Also, perceptual responses will be assessed to investigate how feelings experienced during resistance exercise training are altered relative to different degrees of effort. The hypothesis is that glycemic control will not be affected by the degree of effort, and improvements will be observed regardless of that. Also, it is hypothesized that the degree of effort will be associated with better psychological responses. The secondary aim of this study is to investigate and report adherence rate and reasons for adhering or not to the protocols. It is anticipated that adherence will be associated with the degree of effort and psychological responses experienced during training.

Inclusion criteria

• Living with type 2 diabetes mellitus

Exclusion criteria

• Have a significant cognitive impairment,
• Are non-ambulatory,
• Have lower extremity amputation,
• Have renal failure,
• Have liver disease,
• Have uncontrolled hypertension (>160 mmHg systolic and/or >100 mmHg diastolic),
• Have unstable cardiovascular disease,
• Have a history of severe cardiovascular problems,
• Have decompensated heart failure,
• Have uncontrolled arrhythmias,
• Have severe pulmonary hypertension (mean pulmonary arterial pressure >55 mm Hg),
• Have severe and symptomatic aortic stenosis,
• Have acute myocarditis, endocarditis, or pericarditis,
• Have aortic dissection,
• Have Marfan syndrome,
• Have unrepaired aortic aneurysm,
• Have proliferative diabetic retinopathy,
• Have rapidly progressive terminal illness,
• Are unable to perform resistance exercise to due preexisting musculoskeletal conditions (e.g., joint pain, chronic injury or tendinopathy),
• Are under biguanide (metformin) treatment, but are taking for less than 3 months,
• Have taken drugs known to increase the risk of tendon disorders (e.g., tendinopathy and tendon rupture) within the last 6 months. These drugs include, but may not be limited to: fluoroquinolones, glucocorticoids, aromatase inhibitors, anabolic steroids, antiretrovirals, isotretinoin, cephalexin, rituximab, sitagliptin, cephalosporins, azithromycin, and sulfonamides.
• Are pregnant or trying to become pregnant during the study,
• Are prisoners,
• Are persons that require a legally authorized representative.

Temporary exclusions include:

• Being subjected to recent surgeries for which resistance training is not recommended,
• Have symptomatic hernias,
• Have acute illness,
• Have recent fractures, or other injuries until resolved.