Nieman 1997.

Methods	Study design: factorial randomised controlled trial Location, number of centres: Loma Linda University Center Country: USA Study period: late January to April Methods of analysis: "log books for daily recording of health problems were given to each participant at baseline. Careful verbal and written instructions were given during a pre‐study orientation session. Participants recorded health problems each day of the 12‐week study using codes used in previous studies. The coded health problems included: 1. No health problems today; 2. Cold symptoms (runny, stuffy nose, sore throat, coughing, sneezing, coloured discharge; 3. Flu symptoms (fever, headache, general aches and pains, fatigue and weakness, chest discomfort, cough); 4. Nausea, vomiting and/or diarrhoea; 5. Muscle, joint or bone problems/injury; 6. Other health problems (describe). The severity of the symptoms was rated by participants as mild, moderate or severe. The number of days with URTI symptoms was calculated for each subject, with days counted only if 2 or more consecutive days of cold or flu symptoms were reported with a mild to severe rating. Body mass and composition were determined for all participants by means of underwater weighing. Residual volume was measured by the nitrogen washout procedure using the System 2100 Computerized Pulmonary Function Laboratory (Sensor Medics Corp, Yorba Linda, Calif). Maximal aerobic power (Vo₂ max) was determined using the Bruce graded maximal treadmill protocol (20). Oxygen uptake was measured using the MedGraphics CPX metabolic system (MedGraphics Corporation, St Paul, Minn). Immune assay measurement blood samples were drawn at 7 am from an antecubital vein with participants in the seated position (after 10 to 15 minutes of rest). Routine complete blood counts were performed by clinical haematology laboratory staff using a Coulter STKS instrument (Coulter Electronics, Hialeah, Fla)" Statistical analysis: "statistical significance was set at the P < 0.05 level and values are expressed as mean ± standard deviation. Data analysed using a 4 (control, exercise, diet, exercise+diet groups) x 2 (pre‐ and post‐study) repeated measures ANOVA. Duncan multiple comparison test. Pearson product‐moment correlations for changes in body mass, body mass index, body fat mass and VO₂ max"
Participants	Recruitment means: participants were recruited from the surrounding community through advertisements Target participants: obese females N screened: 102 obese females N completed: 91 completed: 22 (control); 21 (exercise); diet (26); exercise + diet (22) Gender F = 91 Age: 45.6 ± 1.1 Inclusion criteria: "between the ages of 25 and 75 years; in good health with no known diseases, including diabetes, cancer and heart disease; body mass index (BMI, calculated as kg/m²) between 25 and 65 for obese participants and fewer than 25 for non‐obese participants; not currently following a reducing diet or exercise programme not using medications known to affect immune function; not using supplements in excess of 100% of the Recommended Dietary Allowance on a regular basis; not experiencing chronic pain, marked sleep disturbance, serious allergies, salient emotional or mood problems; no recent history of systemic infection, bone fracture, or surgery; and not smoking cigarettes or abusing alcohol" Baseline details: compliance, body composition and immune function, blood cholesterol, triglycerides and glucose
Interventions	Setting of the intervention: indoor track Description of intervention: participants in 2 exercise groups (E and ED) were required to walk 5 times a week, 45 minutes per session, at 60% to 80% of maximum heart rate (MHR) for 12 weeks (60 total exercise sessions). Supervised sessions were held 4 days per week at an indoor track with duration, heart rate, and distance walked measured and recorded. Participants walked 1 session per week without supervision. Duration and intensity of exercise was gradually increased over a 3‐week period from 25 to 30 minutes/session at 60% to 65% MHR during the first week to 45 minutes at 70% to 80% MHR from weeks 4 to 12. Participants in the 2 non‐walking groups (C and D) reported to the exercise facility 4 days week for a 45‐minute session of stretching and mild range‐of‐motion calisthenic exercises. Delivered by: supervised sessions Follow‐up period: 12 weeks Co‐interventions: none
Outcomes	Body composition, aerobic power and immune function, blood cholesterol, triglycerides and glucose, days of URTI Follow‐up period: 12 weeks
Notes	Study funding: this work was funded by The Cybex Grant from the American College of Sports Medicine
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The authors do not explain how the random sequence was generated.
Allocation concealment (selection bias)	Unclear risk	No description of how allocation was concealed. "Before being included in the study, participants had to agree to be randomised to any 1 of the 4 groups (control, exercise, diet, diet and exercise)"
Blinding of participants and personnel (performance bias) All outcomes	High risk	The participants could not be blinded due to the characteristics of the intervention.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Outcomes measured by participant self‐report.
Incomplete outcome data (attrition bias) All outcomes	High risk	There was loss of 10.8% (dropouts), and no intention‐to‐treat analysis was used.
Selective reporting (reporting bias)	Low risk	The outcomes prespecified in the methods were reported in the results.
Other bias	Low risk	The study seems to be free of other sources of bias.