Individually, Nigella sativa (NS) and physical training interventions have been shown to be effective preventive and therapeutic strategies for diabetes mellitus. However, the effect of these in combination on bioindicators of diabetes has not yet been evaluated; there is little information available in the literature. A systematic review was therefore performed to assess any mutually potentiating impacts of NS and physical training interventions in diabetic subjects. A search was performed on this topic in the PubMed, CINAHL, Google Scholar and Web of Science databases for randomised, quasi-randomised or non-randomised controlled trials, studies with factorial or single-cohort pre-post designs, case series as well as case reports. The search terms encompassed various combinations of the following: “exercise”, “training”, “physical activity”, “NS”, “treadmill”, “swimming”, “Thymoquinone”, “Nigellone”, “caraway oil” and “black seeds”. Two reviewers screened the abstracts of 202 identified publications according to predetermined inclusion criteria—i.e. papers published from 2009 onwards in the English language, studies on human or animal subjects, and the assessment of diabetic bioindicators following the combined administration of NS and exercise regimens in comparison with just one of these interventions or against controls. Despite the rich data available regarding the effect of both interventions separately, two human studies and two animal studies were ultimately included in the review. However, the benefit of combined administration of NS and exercise regimens on glycemic and lipidemic control was much more obvious compared to exercise alone. In conclusion, these findings suggested that combined administration of NS and exercise regimens could be used as an effective adjuvant for oral antidiabetic drugs in diabetes control.

Background: This study evaluated the effects of combined exercise (CE) alone and CE combined with Nigella sativa (NS) supplementation on musculoskeletal performance and blood fructosamine levels in male patients with Type 2 diabetes mellitus (T2DM). Methods: Ninety male patients were randomly allocated to one of three groups in a 1:1:1 ratio: a non-exercise comparator (Diabetes), a Diabetes + CE group, or a Diabetes + CE + NS group (n = 30 per group). NS was administered orally (2 g/day) for four weeks. Functional performance outcomes included the six-minute walk test, timed up-and-go test, handgrip strength, and sit-to-stand repetitions. Glycemic control was assessed using blood fructosamine at baseline and after four weeks. Results: Both intervention groups showed significant improvements in all functional outcomes and significant reductions in BMI and fructosamine compared with the non-exercise comparator group (p < 0.05). Post-intervention blood fructosamine was significantly lower in the CE + NS group than in the CE group (p = 0.002). Conclusions: CE significantly improved musculoskeletal performance and short-term glycemic control. The addition of NS appeared to confer additional benefits, particularly on glycemic control and upper- and lower-limb strength, although results should be interpreted with consideration of the short intervention duration, the male-only sample, and reliance on BMI as the body composition measure.

Type 2 diabetes mellitus (T2DM) is increasingly managed through lifestyle measures, yet the value of pairing structured exercise with a well-characterised phytotherapeutic adjunct remains poorly defined. We examined whether adding Nigella sativa (NS) to combined aerobic and resistance exercise (EX) yields greater improvements in metabolic, inflammatory, and oxidative-stress markers than exercise alone in men with T2DM. In this three-arm randomised controlled trial, 90 sedentary, non-smoking men (aged 40–60 years; T2DM duration > 2 years; glycated haemoglobin (HbA1c) 6.5–9.0%; body mass index (BMI) < 30 kg/m²) were allocated 1:1:1 to control, EX, or EX + NS (2 g/day; n = 30 per group) for four weeks. Fasting blood samples obtained before and after the intervention were used to measure glycaemic indices (fasting blood glucose (FBG) and fructosamine), a lipid panel (total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c)), inflammatory markers (tumour necrosis factor-α (TNF-α), interleukin-4 (IL-4), and adiponectin), and oxidative-stress markers (thiobarbituric acid–reactive substances (TBARS) and catalase activity). Outcomes were analysed by two-way repeated-measures analysis of variance (time × group), with partial eta-squared (η_p²) and 95% confidence intervals (CIs) reported for all principal effects. Relative to control, both exercise arms significantly improved body composition and glycaemic, lipid, inflammatory, and oxidative-stress profiles (all p < 0.05). The time × group interaction was significant for every outcome except systolic and diastolic blood pressure and triglycerides. Compared with EX alone, EX + NS produced significantly greater improvements in FBG, HDL-C, TBARS, and catalase activity; changes in fructosamine, total cholesterol, TNF-α, IL-4, and adiponectin favoured EX + NS directionally but did not reach significance after correction for multiple comparisons. Triglycerides, LDL-C, and blood pressure did not differ between the two exercise arms. These hypothesis-generating findings support NS as a candidate adjunct to structured exercise for selected metabolic and redox outcomes, and warrant larger, longer, sex-balanced confirmation.