Introduction
Materials and methods
Results
Authors, year | Study location/name | Study design | Intervention duration | Number of subjects (men/women) | Inclusion criteria | Type of intervention | Type of dietary intervention | Type of exercise intervention | Method of physical activity measurement |
---|---|---|---|---|---|---|---|---|---|
Lindström et al. 2003 [21] | Finland/Finnish Diabetes Prevention Study | RCT | 3 years | 522 (172/350) | IGT (WHO criteria, 1985), age 40–64 years, BMI≥25 kg/m2
| Exercise and diet | Weight reduction through a healthy diet | Participants individually encouraged to increase their overall level of physical activity. Circuit-type exercise sessions were also offered. | Self-report—Kuopio 12 month leisure time physical activity questionnaire |
Knowler et al. 2002 [12] | USA/Diabetes Prevention Research Group | RCT | Average follow-up 2.8 (range 1.8–4.6) years | 2,161 (680/1481)a
| IGT (ADA criteria, 1997), age ≥25 years, BMI ≥24 kg/m2 (≥22 kg/m2 if Asian), fasting plasma glucose ≥5.3 mmol/l | Exercise and diet | Weight reduction through a healthy, low-energy, low-fat diet | Participants individually encouraged to accumulate at least 150 min/week of moderate intensity exercise. | Self-report—Modified Activity Questionnaire and activity log |
Pan et al. 1997 [10] | China/The Da Qing IGT and Diabetes Study | RCT | 6 years | 530 (283/247) | IGT (WHO criteria, 1985), age ≥25 years | 1. Exercise 2. Exercise and diet | Weight maintenance for those with a BMI <25 kg/m2 through a healthy energy-balanced diet; weight reduction for those with a BMI ≥25 kg/m2 through reduced energy intake | Participants were encouraged to increase their physical activity to 1 unit per dayb. Those who were aged <50 years and were able to were encouraged to accumulate 2 units per day. | Self-report—type not reported |
Eriksson and Lindgärde, 1991 [24] | Sweden/The 6-year Malmö feasibility study | Non-randomised controlled trial | 5 years | 260 (260/0) | IGT (2-h post-challenge glucose values 7–11 mmol/l, and fasting plasma glucose <7.8 mmol/l) | Exercise and diet | Healthy dietary advice given | Participants were encouraged to increase their physical activity levels. Participants given the option of training in organised groups for a 6-month period in the first year. |
VO2max—heart rate response to submaximal workload using bicycle ergometer |
Oldroyd et al. 2006 [19] | England | RCT | 2 years | 69 (39/30) | IGT (WHO criteria, 1985) | Exercise and diet | Weight reduction through a healthy, low-energy, low-fat diet | Participants were encouraged to undertake 20–30 min of aerobic activity 2–3 days/week. In addition, all participants were given a discount at local gyms. | Cardiovascular fitness—shuttle test |
Self-report—type not reported | |||||||||
Mensink et al. 2003 [22] | Netherlands/Study on lifestyle-intervention and impaired glucose tolerance Maastricht | RCT | 2 years | 114 (64/50) | IGT (2-h post-challenge glucose values 7.8–12.5 mmol/l, and fasting plasma glucose <7.8 mmol/l), age >40 years, BMI ≥25.0 kg/m2
| Exercise and diet | Weight reduction through a healthy, low-energy, low-fat diet | Participants were encouraged through goal setting to undertake 30 min of moderate intensity exercise per day and were given use of free exercise classes. |
VO2max—incremental exhaustive test using bicycle ergometer |
Lindahl et al. 1999 [23] | Sweden | RCT | 1 year | 186 (69/117) | IGT (WHO criteria, 1985), age 30–60 years, BMI ≥27 kg/m2
| Exercise and diet | Weight reduction through a healthy, low-energy, low-fat diet. | Participants were encouraged to increase their physical activity. Supervised exercise sessions were available in the first month |
VO2max—heart rate response to submaximal and maximal workload using bicycle ergometer |
Carr et al. 2005 [20] | USA | RCT | 2 years | 62 (29/33) | IGT (WHO criteria, 1998) | Structured exercise and diet | Participants were encouraged to follow the energy-balanced American Heart Foundation Step 2 diet | Walking/jogging at >70% of heart rate reserve for 1 h on 3 days/week |
VO2max—modified branching treadmill protocol |
Authors, year | Baseline VO2max (l/min) | Change in VO2max (l/min)a
| Baseline self-reported physical activity levels | Change in self-reported leisure time physical activitya
| Baseline body mass (kg) | Change in body mass (kg)a
| Baseline 2-h plasma glucose (mmol/l) | Change in 2-h plasma glucose from baseline (mmol/l)a
| Baseline fasting glucose (mmol/l) | Change in fasting plasma glucose (mmol/l)a
| Relative risk of diabetes in the intervention group vs the C: group (95% CIs) |
---|---|---|---|---|---|---|---|---|---|---|---|
Lindström et al. 2003 [21] | N/A | N/A | L: 156 (62 to 288) min/week | L: 61 (−33 to 168) min/weekb`
| L: 86.7 ± 0.8 | Results at 3 years | L: 8.9 ± 0.1 | Change at 1 year | L: 6.1 ± 0.05 | Change at 1 year | 0.4 (0.3–0.7) |
C: 169 (65 to 352) min/week | C: 6 (−91 to 104) min/week | C: 85.5 ± 0.9 | L: −3.5 ± 0.3b
| C: 8.9 ± 0.1 | L: −0.9 ± 0.1b
| C: 6.2 ± 0.04 | L: −0.2 ± 0.04 | ||||
C: −0.9 ± 0.4 | C: −0.3 ± 0.1 | C: 0.0 ± 0.04 | |||||||||
Change at 3 years | Change at 3 years | ||||||||||
L: −0.5 ± 0.2 | L: 0.0 ± 0.05 | ||||||||||
C: −0.1 ± 0.2 | C: 0.1 ± 0.05 | ||||||||||
Knowler et al. 2002 [12] | N/A | N/A | L: 15.5 ± 0.7 MET-h/week | L: 6 MET-h/weekb,c
| L: 94.1 ± 0.6 | L: −5.6b
| L: 9.1 ± 0.03 | NR | L: 5.9 ± 0.01 | NR | 0.4 (0.3–0.5) |
C: 17.0 ± 0.9 MET-h/week | C: 1 MET-h/weekc
| C: 94.3 ± 0.6 | C: −0.1 | C: 9.1 ± 0.03 | C: 5.9 ± 0.02 | ||||||
Pan et al. 1997 [10] | N/A | N/A | E: 3.4 ± 0.2 unitsd
| E: 0.6 unitsd
| NR | D&E: −2.5 | E: 8.8 ± 0.1 | E: 1.7 | E: 5.6 ± 0.1 | E: 1.3 | E: 0.5 (0.2–0.9) |
D&E: 3.1 ± 0.2 unitsd
| D&E: 0.8 unitsd
| E: −0.4 | D&E: 9.1 ± 0.1 | D&E 1.7 | D&E 5.7 ± 0.1 | D&E: 1.5 | D&E: 0.6 (0.3–0.9) | ||||
C: 2.4 ± 0.2 unitsd
| C: 0.1 unitsd
| C: −1.0 | C: 9.0 ± 0.1 | C: 4.0 | C: 5.5 ± 0.1 | C: 2.1 | |||||
Eriksson and Lindgärde 1991 [24] | L: 2.46 ± 0.04 | L: 0.20b
| N/A | N/A | L: 82c
| L: −3.3b
| L: 8.2 ± 01 | L: −1.1b
| NR | NR | 0.4 (0.2–0.7) |
C: 2.29 ± 0.1 | C: −0.05 | C: 83c
| C: 0.2 | C: 8.3 ± 0.1 | C: 0.1c
| ||||||
Oldroyd et al. 2006 [19] | N/A | N/A | NR | NR | L: 85.3 ± 2.9 | L: −1.8 ± 1.1b
| L: 9.2 ± 0.1 | Change at 1 year | L: 6.1 ± 0.1 | Change at 1 year | N/A |
C: 85.5 ± 2.5 | C: 1.5 ± 0.5 | C: 9.2 ± 0.2 | L: −0.6 ± 0.3 | C: 6.2 ± 0.2 | L: 0.0 ± 0.1 | ||||||
C: 0.2 ± 0.3 | C: 0.1 ± 0.2 | ||||||||||
Change at 2 years | Change at 2 years | ||||||||||
L: 0.2 ± 0.3 | L: 0.3 ± 0.1 | ||||||||||
C: −0.5 ± 0.4 | C: 0.1 ± 0.2 | ||||||||||
Mensink et al. 2003 [22] | L: 2.15 ± 0.1 | L: 0.09 ± 1.90b
| N/A | N/A | L: 86 ± 1.9 | L: −2.4 ± 0.7b
| L: 8.9 ± 0.3 | Change at 1 year | L: 5.9 ± 0.1 | Change at 1 year | N/A |
C: 2.13 ± 0.1 | C: −0.03 ± 2.77 | C: 83.7 ± 1.5 | C: 0.1 ± 0.5 | C: 8.6 ± 0.2 | L: −0.9 ± 0.3b
| C: 5.8 ± 0.1 | L: −0.1 ± 0.1 | ||||
C: 0.3 ± 0.3 | C: 0.1 ± 0.1 | ||||||||||
Change at 2 years | Change at 2 years | ||||||||||
L: −0.6 ± 0.3b
| L: 0.2 ± 0.1 | ||||||||||
C: 0.8 ± 0.4 | C: 0.5 ± 0.1 | ||||||||||
Lindahl et al. 1999 [23] | L: 2.12 ± 0.1e
| L: 0.21 ± 0.1b,e
| N/A | N/A | L: 86.4 ± 1.1 | L: −5.4 ± 0.5b
| L: 7.5 | L: −0.7 ± 0.2 | L: 5.4 | L: −0.5 ± 0.1 | N/A |
C: 1.89 ± 0.1e
| C: −0.02 ± 0.1e
| C: 83.6 ± 1.1 | C: −0.5 ± 0.3 | C: 8.0 | C: −0.3 ± 0.3 | C: 6.1 | C: −0.3 ± 0.1 | ||||
Carr et al. 2005 [20] | E: 1.93 ± 0.1 | E: 0.16 ± 0.04b
| N/A | N/A | E: 66.5 ± 2.9 | E: −1.8 ± 0.5b
| E: 9.2 ± 0.2 | Change at 6 months | E: 5.3 ± 0.1 | Change at 6 months | N/A |
C: 2.02 ± 0.1 | C: −0.04 ± 0.03 | C: 69.7 ± 2.6 | C: 0.6 ± 0.5 | C: 9.1 ± 0.2 | E: −0.7 | C: 5.4 ± 0.1 | E: 0.0 | ||||
C: −0.1 | C: 0.1 | ||||||||||
Change at 2 years | Change at 2 years | ||||||||||
E: −0.6 | E: 0.0 | ||||||||||
C: 0.0 | C: 0.1 |