Blood flow restricted (BFR) exercise has been shown to improve skeletal muscle adaptations to resistance exercise.  BFR uses blood pressure cuffs (i.e., tourniquets) to reduce skeletal muscle blood flow during resistance exercise.  One benefit of BFR is that skeletal muscle adaptations to resistance exercise training including muscle hypertrophy and increases in strength can be achieved at lower-loads (e.g., 30% 1RM), that are often comparable to more traditional resistance training loads (70-85% 1RM).  However, the impact that low-load BFR resistance exercise has on muscle quality and bioenergetics is unknown.  We propose to examine the impact of 6 weeks of low-load single-leg resistance exercise training with or without personalized blood flow restriction on measures of muscle mass, strength, quality, and mitochondrial bioenergetics.  We will recruit and study up to 30, previously sedentary, healthy, college-aged adults (18-40 years).  We will measure muscle mass using Dual Energy X-Ray Absorptiometry and muscle strength and endurance using isokinetic testing.  We will normalize knee extensor strength to lower limb lean mass to quantify muscle quality.  We will also use near infrared spectroscopy (NIRS) to measure mitochondrial oxidative capacity in the vastus lateralis.  Finally, we will measure markers of systemic inflammation and markers of muscle damage using commercially available ELISA assays.