Vitamin K2 Does Not Speed Muscle Recovery After Weight Training
Graded Moderate — 80 healthy adults were assigned at random to vitamin K2 or a dummy pill for 12 weeks; with a group this small, modest effects could go undetected.
- Design
- Randomized controlled trial
- Participants
- 80
- Duration
- 12 weeks
- Funding
- Medical Research Council; Wellcome Trust
Twelve weeks of vitamin K2 did not change strength or soreness in the days after a hard strength workout, in young or older adults.
Sore, weak muscles can linger for days after a tough strength session. Vitamin K2 has been suggested as a way to recover faster. In this trial it made no measurable difference: strength, everyday movement, soreness and inflammation markers in the blood recovered the same with or without it.
The volunteers were healthy adults aged 18 to 40 and adults aged 65 or older. They were chosen at random to take either 240 micrograms of vitamin K2 or a dummy pill every day for 12 weeks. Of 80 people, 71 finished. Before and after the 12 weeks, everyone did an exercise designed to strain the thigh muscles. The team then tracked strength, soreness and blood values for three days. Vitamin K2 levels in the blood rose clearly.
Only in the older group did small differences appear. Signals between nerve and muscle ran slightly faster, and a blood marker of muscle damage was lower after three days. The authors see these as leads for future research. Whether the vitamin helps frail older people is unclear, because the older adults here were very healthy.
Conflict of Interest Disclosure: One author received research funding from Kappa Bioscience, a company that makes and sells vitamin K2.
Disclaimer: Research summaries are provided for informational purposes only and do not constitute medical advice. Always consult a qualified healthcare professional before making changes to your health routine.