This interventional study was conducted over a 12-week period from July 2022 to September 2022 A time-bound study used a convenient sampling method to select a sample size of 30 subjects. The participants were recruited from the Primary Physiotherapy Outpatient Department of Meenakshi Medical College Hospital Research Institute in Chennai, Tamil Nadu, India.

Outcome measures: WOMAC scale- Scores on this scale range from 0 to 68, where ‘0’ indicates “no disability” and ‘68’ indicates “disability.” The WOMAC includes 24 items divided into three categories: Pain (5 items), Physical Function (17 items), and Stiffness (2 items). Known for its reliability, the WOMAC questionnaire is a tool designed for individuals with OA [20,21].

Prior to participating in the study, all participants provided informed consent. This study has been authorised by the Institutional Review Board, with the number 01/004/2021/ISRB/PGSR/SCPT.

Inclusion criteria: Both men and women aged between 35 and 70, who was experiencing knee pain persisting for at least three months, with HbA1c levels ranging from 6 to 9, and diagnosed with grade 2 or 3 OA of the knee according to the Kellgren-Lawrence scale [22], must express a willingness to take part in the study.

Exclusion criteria: Patients with severe cardiac and pulmonary conditions, structural abnormalities such as pronated foot, genu valgum and varum, coxa vara and valga, and hallux valgus, traumatic injuries, chronic diabetes with present foot ulcers, neurological abnormalities, uncontrolled hypertension, inflammatory joint diseases like rheumatoid arthritis, osteomyelitis, significant surgical reconstruction performed on a joint in the lower extremity, grade 4 knee OA as per the Kellgren-Lawrence scale, and inability to walk, were excluded from the study.

The examination of participants occurred only after securing their prior consent and providing a clear explanation of the study’s objectives. Detailed information regarding the study’s risk factors, safety measures, and methodology was provided. A total of 30 participants were selected using a convenience sampling technique. Written consent was obtained from each subject after briefing them on the safety and simplicity of the procedure.

Group-A: The experimental group consisted of fifteen participants who performed dynamic resistance exercises with elastic bands that targeted several joints. These exercises involved knee joint flexion and extension, ankle joint plantarflexion and dorsiflexion, external and internal rotation, as well as hip joint abduction, adduction, and flexion and extension [23].

Participants engaged in 10 repetitions per set, completing five sets daily, three days a week, for a total of 12 weeks. The exercises focused on hip abduction/adduction, hip flexion/extension, hip external and internal rotation, knee joint flexion/extension, and ankle plantar/dorsiflexion, using elastic bands to provide resistance.

Group-B: The control group, consisting of 15 subjects, engaged in isometric resistance exercises targeting identical joints. These motions included knee joint flexion/extension, ankle joint plantar/dorsiflexion, external and internal rotation, hip abduction/adduction, and flexion/extension [23]. Participants in this group performed the same exercise movements as those in the dynamic group, but without the use of elastic bands. Instead, they conducted active joint Range Of Motion (ROM) exercises using their body weight and isometric contraction exercises while seated. The regimen consisted of five sets of ten repetitions, with a ten-second hold, performed three times a week for 12 weeks.

Additionally, participants underwent weekly assessments to track exercise adherence and physical activity levels. Both groups were advised on the importance of weight reduction, maintaining a balanced diet, and avoiding prolonged standing. All exercise sessions and instructions were conducted in the physiotherapy outpatient department. Prior to the initiation of treatment, participants underwent pre-test measurements of HbA1c, and post-test measurements were conducted at the end of the 3-month period. Before each treatment session, participants completed the WOMAC scale as a pre-test outcome measure. The procedure was explained to the participants after they had been seated for a few minutes, and the therapist then demonstrated the exercises. Post-treatment outcomes were measured using the same protocol as the pre-test, with the WOMAC scale repeated for assessment.

HbA1c analysis: HbA1c serves as an indicator of the average plasma sugar level over the past three months and is commonly used to monitor individuals with T2DM [24,25]. The usual HbA1c range for non-diabetics is from 4.0% to 5.6%. HbA1c levels ranging from 5.7% to 6.4% indicate prediabetes, while levels of 6.5% or higher suggest diabetes [26]. Physical activity level was self-reported by subjects using SGPALS, Saltin-Grimby physical activity level scale [27]. Each group received detailed explanations of their respective treatment procedures. Group-A participated in dynamic resistance exercise sessions, while Group-B engaged in isometric resistance exercise sessions.

To calculate the mean and Standard Deviation (SD) of HbA1c levels for both the pre-test and post-test in each group, a paired t-test was used to determine the significance of changes within each group from pre-test to post-test. An independent t-test was employed to compare the post-test HbA1c levels between Group-A and Group-B. To calculate the mean and SD of WOMAC scores for both the pre-test and post-test in each group, a paired t-test was used to determine the significance of changes within each group from pre-test to post-test. An independent t-test was conducted to compare post-test WOMAC scores between Group-A and Group-B. The alpha level was set at 0.05 for all tests, and p-values were calculated to assess the significance of the results. StatPro software was used for data analysis.

The participants included in the study were in the age range of 50-70 years. The total number of males were 20 (60%) and females were 10 (40%). Mean duration of type 2 diabetes was 10 years, with a range of 5-20 years. Mean duration OA of the Knee was five years, with a range of 2-10 years. The mean BMI was 28 kg/m², with an average range of 24-32 kg/m². Oral Hypoglycaemics were used by 26 (70%) and 4 (30%) were on insulin therapy.

[Table/Fig-1] presents the pre-test and post-test values of the WOMAC scale for two groups, Group-A and Group-B, involved in the study. For Group-A, the mean pre-test WOMAC score was 51.66, with a SD of 5.33. Following the intervention, the mean post-test WOMAC score decreased to 41.87, with an SD of 3.71. The calculated t-value for this group was 10.35, and the change was statistically significant, with a p-value of less than 0.001.

In Group-B, the mean pre-test WOMAC score was 62.70, with an SD of 4.93. After the intervention, the mean post-test WOMAC score decreased to 51.17, with an SD of 1.70. The t-value for Group-B was 6.32, and this improvement was also statistically significant, with a p-value of less than 0.001.

These results indicate significant improvements in functional performance, as measured by the WOMAC scale, for both groups following their respective exercise interventions.

[Table/Fig-2] summarises the post-test values of the WOMAC scale for Group-A and Group-B following their respective exercise interventions. Group-A, which performed dynamic resistance exercises, had a mean post-test WOMAC score of 41.87 with a SD of 3.71. In contrast, Group-B, which participated in isometric resistance exercises, had a mean post-test WOMAC score of 51.17 with an SD of 1.70.

The t-value for the comparison between the two groups was 5.88, indicating a statistically significant difference in the post-test WOMAC scores. The p-value ≤0.001, demonstrated the improvement in functional performance was significantly more in Group-A compared to Group-B. This suggests that dynamic resistance exercises were more effective in enhancing functional performance in individuals with T2DM and OA of the knee joint.

[Table/Fig-3] provides the pre-test and post-test values for Group-A, which underwent dynamic resistance exercises, while Group-B participated in isometric resistance exercises.

For Group-A, the mean pre-test value was 8.23, with a SD of 1.13. After the intervention, the mean post-test value decreased to 6.76, with an SD of 0.68. The t-value for this change was 8.92, indicating a highly significant improvement, with a p-value of less than 0.001.

Similarly, Group-B had a mean pre-test value of 8.70, with an SD of 1.11. Following the intervention, the mean post-test value reduced to 7.77, with an SD of 1.01. The t-value for this reduction was 8.68, also demonstrating a highly significant improvement, with a p-value of less than 0.001.

Both groups showed significant improvements from pre-test to post-test, with Group-A showing a slightly larger reduction in the mean value. This suggests that while both isometric and dynamic resistance exercises were effective, dynamic resistance exercises may have a marginally greater impact on the measured parameter in individuals with T2DM and OA of the knee joint.

[Table/Fig-4] summarises the post-test values of HbA1c for Group-A and Group-B after their respective exercise interventions. Group-A, which performed dynamic resistance exercises, had a mean post-test HbA1c value of 6.76 with a SD of 0.68. In contrast, Group-B, which participated in isometric resistance exercises, had a mean post-test HbA1c value of 7.77 with an SD of 1.01.

The t-value for the comparison between the two groups was 3.20, indicating a statistically significant difference in the post-test HbA1c values. The p-value associated with this t-value was 0.0033, demonstrating that the reduction in HbA1c was significantly greater in Group-A compared to Group-B. This suggests that dynamic resistance exercises were more effective in lowering HbA1c levels in individuals with T2DM and OA of the knee joint.

The aim and objective of the study were to alleviate pain, enhance functional performance, and decrease HbA1c levels in individuals diagnosed with T2DM and OA of the knee joint. The primary outcome measure utilised was the WOMAC scale, which includes subscores for pain, stiffness, and physical function. HbA1c levels were employed to assess glycaemic control.

OA is the most common form of arthritis, particularly prevalent among the elderly, leading to discomfort and inflammation due to the involvement of articular cartilage, soft-tissues, and bone. In older adults, OA is a primary cause of impairment, as the weakening of the quadriceps muscle reduces joint protection and increases stress on the knee. Strengthening exercises targeting the quadriceps muscles have been shown to enhance knee joint function.

According to O’Connor MI and Hooten EG, resistance exercises have been widely employed as a rehabilitation protocol for individuals with knee OA to enhance muscle strength and alleviate pain [28]. Anzari N highlighted OA as the most common type of arthritis, particularly affecting older individuals [29].

In summary, this study addresses the pressing need to explore effective exercise interventions for managing pain and improving functional outcomes in individuals with T2DM and knee OA, given the considerable impact of these conditions on quality of life and mobility in the older population.

According to Pawar P et al., their study revealed a reduction in pain and stiffness, along with enhancements in physical function among participants, as measured by the WOMAC [30].

Pal CP et al., conducted a cross-sectional study to determine the prevalence of knee OA in India [22]. The study encompassed five sites, each divided into large cities and smaller cities, with a total sample size of 5,000 subjects. The diagnosis of OA was confirmed using plain radiographs and the Kellgren and Lawrence scale.

Misra A et al., showed that the glycaemic index improves with resistance training. They found that training involving major muscle groups was effective in improving glycaemic control and reducing fasting blood sugar levels [31].

According to Tuomilehto J et al., lifestyle adjustments, encompassing physical activity, exercise, counseling, and dietary changes, demonstrate beneficial effects in individuals with T2DM [32]. Moreover, it has been recognised that obesity serves as a risk factor for diabetes.

Imoto AM et al., found that including quadriceps strengthening exercises in a rehabilitation program effectively improved function, pain, and various aspects of quality of life in a population with knee OA [33].

Geirsdottir OG et al., conducted a study that revealed a 12-week resistance exercise program improves muscle strength and muscle function to a similar extent in healthy individuals, those with prediabetes, and elderly individuals with T2DM [34].

According to Chen SM et al., their study involved both genders and consisted of an experimental group with 36 participants and a control group with 34 participants [35]. The experimental group underwent resistance exercises three times a week for 12 weeks, while the control group performed isometric contraction exercises with the same frequency and duration. The study employed a quasi-experimental design and utilised the WOMAC physical function subscale as a measure.

Results indicated significant improvements in dynamic balance, muscle strength, and physical function among participants with knee OA who engaged in dynamic resistance training compared to those who performed isometric exercises. In particular, the experimental group outperformed the control group in improving outcomes for knee OA, as evidenced by higher scores on the WOMAC physical function subscale (62.3% vs. 36.1%) and total WOMAC scores (54 vs. 34.5%).

The researchers investigated the effects of dynamic resistance training versus isometric resistance training on lower limb muscular strength, functional activities, and HbA1c levels in people with T2DM and knee OA. According to the present study findings, a 12-week dynamic resistance training programme significantly improved WOMAC scores, which measure pain, stiffness, and physical function associated with OA in the knee.

Crucially, no participant experienced any adverse responses during the course of the trial. Every participant in the study was also extensively monitored at each session to ensure their safety and track their progress. These findings suggested that these exercises can help individuals with co-morbid T2DM and knee OA improve their functional outcomes and symptoms without any negative side-effects.

The findings from this experimental study comparing the effects of isometric and dynamic resistance exercises on HbA1c and functional performance in patients with T2DM and knee OA have several important clinical implications: both isometric and dynamic resistance exercises were effective in reducing knee pain and improving physical function; dynamic exercises showed greater improvements in muscle strength, which is crucial for joint stability and overall physical function; educating patients about the benefits of resistance exercises and encouraging regular participation can enhance adherence to exercise regimens; and highlighting the specific benefits, such as improved blood sugar levels and reduced knee pain, can motivate patients to engage more consistently in physical activity.

Certainly, it’s important to acknowledge the limitations of this study. Firstly, the relatively small sample size may restrict the broader applicability of the results. Additionally, the brief duration of the study might not fully elucidate the enduring impacts of the intervention. Moreover, the absence of long-term follow-up limits our understanding of the sustained impact of the observed improvements over time.

Some of the confounding factors in this study include age, gender, and the duration and severity of both T2DM and OA, as these can affect baseline measures and exercise response. Baseline physical activity levels, medication use, dietary habits, and Body Mass Index (BMI) can also influence outcomes. Furthermore, adherence to the exercise regimen, psychological factors such as motivation and stress, socio-economic status, smoking and alcohol use, and genetic predispositions might potentially impact the study results.

However, further research is warranted to explore the underlying mechanisms and to confirm these benefits over a longer duration. These constraints should be addressed by using larger sample sizes and longer study periods. This would enable stronger conclusions about the intervention’s efficacy and sustainability. Additionally, examining the results of combining aerobic and resistance training may offer new perspectives on possible synergistic effects on outcomes related to T2DM and knee OA. In general, resolving these issues will advance our understanding of the advantages of exercise treatments for this population.

According to the study’s findings, dynamic resistance training regimen significantly reduced pain, improved functional capability in individuals with knee OA, and decreased HbA1c levels. These results imply that a dynamic resistance training programme for people with T2DM and knee OA leads to modest improvements in both clinical and subjective outcomes. The study also suggests that this type of treatment may be more effective than other programs in managing type 2 diabetes in conjunction with knee OA.