Ligandrol SARM Reduces Endurance and Disrupts Hormones in Male Rats
New study reveals popular bodybuilding supplement ligandrol impairs cardiovascular fitness and hormonal health despite muscle strength gains.
Summary
Researchers tested ligandrol (LGD-4033), a popular but unregulated bodybuilding supplement, in male rats over 8 weeks. While ligandrol increased grip strength, it significantly reduced endurance capacity, maximal oxygen consumption, and testosterone levels. The compound also worsened lipid profiles by increasing triglycerides and cholesterol. Surprisingly, combining ligandrol with endurance training offered no advantages over training alone and actually diminished some training benefits. These findings challenge the widespread belief that SARMs are safer alternatives to anabolic steroids.
Detailed Summary
This controlled study investigated ligandrol (LGD-4033), one of the most popular selective androgen receptor modulators (SARMs) used illegally by bodybuilders and athletes. Despite being banned by WADA and not approved for human use, SARMs are widely available online and increasingly detected in doping tests.
Researchers divided 40 male rats into four groups: sedentary controls, sedentary with ligandrol (0.4 mg/kg, 5x/week), training controls (40 min treadmill, 5x/week), and training plus ligandrol. After 8 weeks, they measured comprehensive fitness, metabolic, and hormonal parameters.
The results revealed concerning trade-offs. While ligandrol increased grip strength, it significantly impaired cardiovascular fitness. Submaximal endurance decreased, and maximal oxygen consumption (VO2max) dropped compared to controls. Ligandrol also disrupted hormonal balance, reducing testosterone and follicle-stimulating hormone levels. Metabolically, the compound worsened lipid profiles by increasing triglycerides and total cholesterol while decreasing glucose levels.
Most surprisingly, combining ligandrol with endurance training provided no advantage over training alone. In fact, ligandrol appeared to blunt some training adaptations, reducing VEGF-a gene expression (important for blood vessel formation) and decreasing the size of type I and IIa muscle fibers in trained animals. Training alone produced superior results across multiple fitness parameters.
These findings challenge the popular notion that SARMs offer muscle-building benefits without the cardiovascular and hormonal risks of anabolic steroids. The study suggests that ligandrol's negative effects on endurance, lipid metabolism, and hormone production may outweigh its modest strength benefits, particularly for athletes focused on cardiovascular performance.
Key Findings
- Ligandrol reduced submaximal endurance capacity and maximal oxygen consumption (VO2max) compared to controls
- Testosterone levels decreased significantly in ligandrol-treated rats versus vehicle controls
- Follicle-stimulating hormone (FSH) concentrations dropped with ligandrol treatment
- Triglycerides and total cholesterol increased in ligandrol groups, worsening lipid profiles
- Grip strength increased with ligandrol treatment, confirming some anabolic effects
- Blood glucose levels decreased in ligandrol-treated animals
- Training plus ligandrol showed no advantage over training alone across multiple parameters
Methodology
Controlled study of 40 fourteen-week-old male Wistar rats divided into four groups (n=10 each) over 8 weeks. Ligandrol administered subcutaneously at 0.4 mg/kg five times weekly. Training groups performed 40-minute treadmill sessions at 25 m/min, 5° incline, five days weekly. Comprehensive assessment included functional tests (VO2max, endurance, grip strength), hormonal analysis, lipid profiles, histological examination, and gene expression analysis using ANOVA with post-hoc testing.
Study Limitations
Study conducted in rats, so human applicability requires confirmation through clinical trials. Eight-week duration may not capture long-term effects. Dosing based on online product concentrations may not reflect optimal therapeutic ranges. Authors noted no conflicts of interest. Sample size was relatively small (n=10 per group) and limited to male subjects only.
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