You know that burn in your legs at the end of a hard interval — the one that makes you back off the pace right when it matters most? That's acid buildup in your muscles, and most athletes just accept it as a ceiling on how hard they can push. Here's what the pros figured out a long time ago: you can raise that ceiling with the right amino acid. Thorne Beta-Alanine SR is the go-to supplement for athletes who want to go harder, longer — especially in the efforts that hurt most. Targets the Burn at Its Source Beta-alanine is the amino acid your body uses to produce carnosine — a compound stored in muscle that neutralizes the acid buildup that causes that deep, heavy fatigue. More carnosine means more time before your muscles hit the wall. Sustained-Release Delivery via PureTab® Technology Standard beta-alanine can cause an intense (and harmless) skin-tingling sensation when taken in effective doses. Thorne's PureTab® sustained-release system delivers beta-alanine gradually, keeping blood levels steady, maximizing absorption, and minimizing the tingle — without sacrificing effectiveness. NSF Certified for Sport Every batch is tested for banned substances and label compliance. If you race or compete, this is non-negotiable. Beta-alanine is what your body uses to produce carnosine — a natural acid buffer stored in muscle tissue that keeps fatigue at bay during hard efforts. Research shows the biggest gains in anaerobic efforts lasting 1–4 minutes and aerobic efforts longer than 4 minutes. Carnosine levels run lower in women, vegetarians, and older athletes, so those groups often see the most pronounced benefit. How to Use Thorne Beta Alanine-SR Daily dose: Take 2 tablets once or twice daily, with or without food. Consistency is the key: Beta-alanine works by building carnosine levels over time — effects compound over several weeks of regular use, not overnight. Pro tip: If you notice any mild skin tingling, it's harmless. The SR format significantly reduces this, but splitting your dose (morning and afternoon) minimizes it further. Thorne is the supplement partner of choice for over 100 professional sports teams and is the most recommended clinical supplement brand by healthcare practitioners. Beta-Alanine SR uses the same SR CarnoSyn® form studied in clinical trials showing performance improvements in cyclists, rowers, and sprint athletes. Stop leaving performance on the table at the end of your hardest efforts — Thorne Beta-Alanine SR is the clinically-backed, NSF-certified tool that lets you push deeper into the red without hitting the wall.
