You won't be able to properly manage your time or set boundaries at work if you can't say "no" when necessary, writes Maria Elena Duron. It's important to be assertive yet polite when turning down extra work, Duron advises.

If you know who you'd turn to for a job if you were laid off or if you feel you have other options besides your current employer, you've managed your career well, writes Alison Green. Professionals who manage their careers appropriately also tend to enjoy their work and are trusted advisers to others in their networks.

While it's good to make a first impression, it's more important to focus on adding value for others over the long term, writes Danny Iny. You shouldn't feel you have only one chance to impress another person, Iny writes.

The AARP sued the Equal Employment Opportunity Commission, claiming regulations governing wellness program incentives will lead to an invasion of employees' medical privacy. The lawsuit claims wellness incentives linked to program participation really are penalties for employees who do not want to share their medical information with employers, making such programs involuntary and a violation of federal law.

Those with degrees and coursework in liberal arts or humanities can take advantage of a recent employer focus on soft skills, writes Nikki Waller. A National Association of Colleges and Employers study found that 2015 graduates with liberal arts degrees had higher employment rates and salaries than those from 2014.

You can feel healthier and more energetic at work simply by having a more nutritious diet that includes less caffeine, writes Mark Kishel. Try to get plenty of sleep at night while exercising regularly and getting regular health screenings, Kishel writes.