Eligibility Criteria:
For Overweight phase:
Inclusion Criteria:
* Volunteers: men and women from Comunidad de Madrid (Zone 5 of Health System) who sign the informed consent.
* Ages 18 - 50 years old.
* Pre-menopausal.
* Body mass index (BMI) of 25 - 30 kg•m-2 (both included).
* Able to attend exercise classes 3 times per week (Monday, Wednesday and Friday). No plans for excessive travel. No plans to move from area for study period (January 2010 - June 2010, both included).
* Able to follow the nutritional treatment (avoid medication or substances known to interfere with body weight regulation, including anti-depressive medication, diuretics, etc., 15 days before study starts).
* Willing to not participate in other formal or informal weight loss program during the period of the study.
* Sedentary (less than once a week of training or two hours of physical activity class).
Exclusion Criteria:
* Smoking within six months, or use of tobacco or nicotine product.
* Women with irregular menstrual cycle (except with hormone therapy).
* Following a weight loss diet, vegetarians or food restriction due to religion.
* Self-reported weight loss or gain \>5% in past 6 months.
* Are not pregnant, or haven´t been in the past six months. Are not currently nursing or planning to become pregnant during the study period (year 2010).
* Need a special diet by associated disease (celiac disease or chronic renal insufficiency).
* Have metabolic syndrome or fulfill three or more of the following criteria: abdominal obesity (waist diameter \> 102 cm in men and \> 88 cm in women), blood pressure ≥ 130/85 mm Hg, basal glycemia ≥ 110 mg/dL, triglyceride level \> 150 mg/dL and C-HDL \< 40 mg/dL in women and \< 50 mg/dL in men.
* Diabetes.
* Anemia (Hct \< 37%).
* Uncontrolled high blood pressure (Systolic \> 160 mm Hg or diastolic \> 100 mm Hg in rest). Current use of more than one anti-hypertensive medication.
* Substance abuse (drugs, alcohol…). High or moderate consumes of alcohol. More than 2 glasses to the day of any alcoholic substance. Current use of diuretics, beta blockers, steroids or blood thinners.
* Contraindication to exercise. Alterations, syndromes or diseases detected by electrocardiogram (EKG) o echocardiography. Have injuries o pathologies of the locomotive apparatus that prevent the correct execution of the exercises of the program. Any illness that would prevent participation in a moderate-intense exercise program.
* Have had cancer in the past 5 years, except skin cancer.
* Coronary artery disease, liver disease, pulmonary disease, renal disease or other systemic disorders.
* History or evidence of cardiovascular disease, alterations, syndromes or other mayor chronic illness. Have history of heart disease, heart attacks or heart surgery.
* Have any illness known to interfere with body weight loss: clinical depression, eating disorder (anorexia, bulimia, etc.), psychological diseases (schizophrenia, etc.), dementia or cognitive function decreased, hypothyroidism no controlled or history of genetic or chromosomal disorder.
* Have had bariatric surgery or stomach bypass surgery.
* Gross physical impairment.
* Blindness or retinopathy.
For Obese phase:
Inclusion Criteria:
* Volunteers: men and women from Comunidad de Madrid (Zone 5 of Health System) who sign the informed consent.
* Ages 18 - 50 years old.
* Pre-menopausal.
* Body mass index (BMI) of 30 - 35 kg•m-2 (both included).
* Able to attend exercise classes 3 times per week (Monday, Wednesday and Friday). No plans for excessive travel. No plans to move from area for study period (January 2011 - June 2011, both included).
* Able to follow the nutritional treatment (avoid medication or substances known to interfere with body weight regulation, including anti-depressive medication, diuretics, etc., 15 days before study starts).
* Willing to not participate in other formal or informal weight loss program during the period of the study.
* Sedentary (less than once a week of training or two hours of physical activity class).
Exclusion Criteria:
* Smoking within six months, or use of tobacco or nicotine product.
* Women with irregular menstrual cycle (except with hormone therapy).
* Following a weight loss diet, vegetarians or food restriction due to religion.
* Self-reported weight loss or gain \>5% in past 6 months.
* Are not pregnant, or haven´t been in the past six months. Are not currently nursing or planning to become pregnant during the study period (year 2011).
* Need a special diet by associated disease (celiac disease or chronic renal insufficiency).
* Have metabolic syndrome or fulfill three or more of the following criteria: abdominal obesity (waist diameter \> 102 cm in men and \> 88 cm in women), blood pressure ≥ 130/85 mm Hg, basal glycemia ≥ 110 mg/dL, triglyceride level \> 150 mg/dL and C-HDL \< 40 mg/dL in women and \< 50 mg/dL in men.
* Diabetes.
* Anemia (Hct \< 37%).
* Uncontrolled high blood pressure (Systolic \> 160 mm Hg or diastolic \> 100 mm Hg in rest). Current use of more than one anti-hypertensive medication.
* Substance abuse (drugs, alcohol…). High or moderate consumes of alcohol. More than 2 glasses to the day of any alcoholic substance. Current use of diuretics, beta blockers, steroids or blood thinners.
* Contraindication to exercise. Alterations, syndromes or diseases detected by electrocardiogram (EKG) o echocardiography. Have injuries o pathologies of the locomotive apparatus that prevent the correct execution of the exercises of the program. Any illness that would prevent participation in a moderate-intense exercise program.
* Have had cancer in the past 5 years, except skin cancer.
* Coronary artery disease, liver disease, pulmonary disease, renal disease or other systemic disorders.
* History or evidence of cardiovascular disease, alterations, syndromes or other mayor chronic illness. Have history of heart disease, heart attacks or heart surgery.
* Have any illness known to interfere with body weight loss: clinical depression, eating disorder (anorexia, bulimia, etc.), psychological diseases (schizophrenia, etc.), dementia or cognitive function decreased, hypothyroidism no controlled or history of genetic or chromosomal disorder.
* Have had bariatric surgery or stomach bypass surgery.
* Gross physical impairment.
* Blindness or retinopathy.