Sales people need to eat better, exercise regularly and sleep more to successfully sell.
Sounds a little random, but it is VERY difficult when working in the high pressure and busy world of selling to maintain a healthy diet, find time to exercise and to be able to get the recommended amount of sleep.
That being said I don't think many sales people full appreciate the impact it will be having on their results.
I'd highly recommend that sales people make more effort but I would also recommend that companies make more effort to support this as well. This could include having fruit around the office, water, discounted or provided gym membership, morning exercise sessions and regular debriefs to ensure people don't go home stressed.
I've always been passionate about this but reading it in“Sales EQ“ by Jeb Blount made me realise how many sales people probably don't take it seriously enough.
Make small little changes in those areas and you'll find more energy, more confidence and more positivity which will all help drive more sales.