Research

Energy balance

Aerobic exercise training in the absence of weight loss does not significantly improve fasting glucose, fasting insulin, or lipoprotein concentrations (HDL-C, LDL-C) compared to a control group, although it does increase VO2max.

If you start exercising but do not lose weight, your cardiovascular fitness will likely improve, but your blood sugar, insulin, and cholesterol levels may not change significantly. To fix metabolic health markers, you must also lose weight through diet.

GoodRefutesHIGH confidence
By contrast, aerobic exercise did not improve fasting glucose or insulin concentrations or glucose responses during the OGTT... Although there was a modest 5% increase in HDL-C levels (within-group paired t test; P<.05) with training, this did not differ from the control group.
Leslie I. Katzel · JAMA · 1995

Why this rating

RCT design, clear negative findings for specific metrics.

Source

Effects of Weight Loss vs Aerobic Exercise Training on Risk Factors for Coronary Disease in Healthy, Obese, Middle-aged and Older Men

Leslie I. Katzel · JAMA · 1995

DOI 10.1001/jama.1995.03530240025035

rct · n=170Cited 295×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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