The acute effects of interval- Vs continuous-walking exercise on glycemic control in subjects with type 2 diabetes: a crossover, controlled study.
Study Goal
The researchers aimed to determine whether interval walking improves postprandial glucose tolerance and free-living glycemia more effectively than continuous walking in individuals with type 2 diabetes.
Results Summary
Interval walking (IW) significantly reduced mean and maximal incremental plasma glucose levels compared to both continuous walking (CW) and control (CON), and improved metabolic clearance rate. IW also lowered mean glucose levels for the rest of the intervention day compared to CW, though no differences were observed the following day.
Population
10 individuals diagnosed with type 2 diabetes mellitus.
Effective Dosage
Three 1-hour interventions (interval walking, continuous walking, and control).
Duration
1-hour sessions with follow-up measurements over approximately 32 hours.
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
interval walking | decrease | mean incremental plasma glucose during the MMTT | patients diagnosed with type 2 diabetes mellitus | 1.2 ± 0.4 vs 2.0 ± 0.5 mmol/L | decreased | #1 |
interval walking | decrease | maximal incremental plasma glucose during the MMTT | patients diagnosed with type 2 diabetes mellitus | 3.7 ± 0.6 vs 4.6 ± 0.7 mmol/L | decreased | #2 |
interval walking | decrease | mean incremental plasma glucose during the MMTT | patients diagnosed with type 2 diabetes mellitus | 1.2 ± 0.4 vs 1.7 ± 0.4 mmol/L | decreased | #3 |
continuous walking | no change | mean incremental plasma glucose during the MMTT | patients diagnosed with type 2 diabetes mellitus | no differences | showed no differences | #4 |
continuous walking | no change | maximal incremental plasma glucose during the MMTT | patients diagnosed with type 2 diabetes mellitus | no differences | showed no differences | #5 |
interval walking | increase | metabolic clearance rate of glucose during the MMTT | patients diagnosed with type 2 diabetes mellitus | - | increased | #6 |
interval walking | decrease | continuous glucose monitoring mean glucose for the rest of the intervention day | patients diagnosed with type 2 diabetes mellitus | 8.2 ± 0.4 vs 9.3 ± 0.7 mmol/L | reduced | #7 |
interval walking | no change | continuous glucose monitoring mean glucose the following day | patients diagnosed with type 2 diabetes mellitus | no differences | no differences were found | #8 |
one interval-based exercise session | increase | glycemic control | type 2 diabetes mellitus subjects | - | improves | #9 |
CONTEXT: Glycemic control improves with physical activity, but the optimal exercise mode is unknown. OBJECTIVE: The objective of the study was to determine whether interval-based exercise improves postprandial glucose tolerance and free-living glycemia more than oxygen consumption- and time duration-matched continuous exercise. DESIGN: This was a crossover, controlled study with trials performed in randomized order. SETTING: The study was conducted in hospitalized and ambulatory care. PATIENTS: PATIENTS diagnosed with type 2 diabetes mellitus (n=10, no withdrawals) participated in the study. INTERVENTIONS: Subjects performed three 1-hour interventions: 1) interval walking (IW; repeated cycles of 3 min of slow and fast walking); 2) continuous walking (CW); and 3) control (CON). Oxygen consumption (VO2) was measured continuously to match mean VO2 between exercise sessions (∼75% VO2peak). MAIN OUTCOME MEASURES: A mixed-meal tolerance test (MMTT; 450 kcal, 55% carbohydrate) with stable glucose isotopic tracers was provided after each intervention, and glucose kinetics were measured during the following 4 hours. Free-living glycemic control was assessed for approximately 32 hours after the MMTT using continuous glucose monitoring. RESULTS: VO2 was well matched between the exercise interventions. IW decreased the mean and maximal incremental plasma glucose during the MMTT when compared with the CON (mean 1.2 ± 0.4 vs 2.0 ± 0.5 mmol/L, P < .001; maximal 3.7 ± 0.6 vs 4.6 ± 0.7 mmol/L, P = .005) and mean when compared with CW (1.7 ± 0.4 mmol/L, P = .02). No differences in the mean or maximal incremental plasma glucose values were seen between the CW and CON. The metabolic clearance rate of glucose during the MMTT was increased in the IW compared with CW (P = .049) and CON (P < .001). Continuous glucose monitoring mean glucose was reduced in IW compared with CW for the rest of the intervention day (8.2 ± 0.4 vs 9.3 ± 0.7 mmol/L, P = .03), whereas no differences were found between IW and CW the following day. CONCLUSIONS: One interval-based exercise session improves glycemic control in type 2 diabetes mellitus subjects when compared with an oxygen consumption- and time duration-matched continuous exercise session.