Single-Arm Resistance Training and Subcutaneous Fat: Localized vs Whole-Body Fat Loss by MRI
Kostek MA, Pescatello LS, Seip RL, et al.
Evidence is still building up
Summary
In 104 participants (45 men, 59 women) who trained the non-dominant arm for 12 weeks with the contralateral arm as a within-subject control, skinfold calipers showed a reduction only in the trained arm of men (suggesting spot reduction), but the more precise MRI detected generalized whole-body subcutaneous fat loss regardless of sex, refuting localized spot reduction.
Key findings
- 1
Skinfold calipers showed fat loss only in the trained arm of men, superficially suggesting spot reduction
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The more precise MRI detected generalized whole-body subcutaneous fat loss regardless of sex, refuting localized spot reduction
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A single-arm design with the contralateral arm as a within-subject control; the difference in measurement sensitivity drove the conclusion
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n=104 is sizeable but this is a single study; classified as an RCT because it has a control (moderate confidence)
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