I read in a book by Steve Maxwell (a pretty well-known exercise and fitness hard-arse) a simple hack to counter workout intensity – smiling.
Next time you see someone grunting or contorting their face (you know the type – jogging or riding a bicycle and looking like they are literally on the brink of death) think of this.
Steve maintains smiling helps reduce stress by stimulating the release of endorphins – being natural painkillers, they can help workout stress (actual and attitudinal) during intense workouts. In addition smiling may also trigger the parasympathetic nervous system (PNS), which is responsible for the body’s rest and digest response. Promoting a higher vagal tone is a whole field of research now – but wisdom from Yoga, Tai Chi, Qigong prove the knowledge is ancient.