The National Park and Recreation Association's annual convention is underway this week in Las Vegas, Nev. After arriving Monday afternoon and getting my first taste of life in the City of Lights, I caught a brief glimpse of the sun and the strip before steeling myself for a day of windowless sessions in overly air-conditioned rooms.

Thankfully, the NRPA conference team knows how to make you forget those details. The opening session, featuring U.S. Surgeon General Vivek H. Murthy, 8 80 Cities founder Gil Penalosa, NRPA chairs past and present and a special musical performance by The Water Cooler, set the mood for another great conference and reminded everyone in attendance what they were really here for. While the full impact of parks and recreation professionals on their communities and the people they serve may be too complex to quantify, there were some numbers from the opening session that can help put it into perspective:

50: The anniversary being celebrated this year by the NRPA. Founded 50 years ago on the pillars of health and wellness, conservation and social equity, the same pillars driving the organization's efforts today, according to NRPA president and CEO Barbara Tulipane.

2 (or 3, depending on who you ask and where in the room you were sitting; I'm short and couldn't get a good view): the number of NRPA conference attendees also celebrating 50 years of membership.

50,000: Approximate number of current NRPA members.

22: Number of minutes of moderate activity, on average, needed to reduce a person's risk for diabetes and heart disease, according to Surgeon General Murthy as he reinforced the message in Step It Up!, a call to action released last week promoting walking and building walkable communities. The message is simple: “We need to reclaim a culture of physical activity in America.”

140 billion: Value, in dollars, of economic activity generated by local and regional parks, according to the latest research reports from NRPA.

1.5 million: The number of people for whom NPRA Board of directors chair-elect Susan Trautman aims to increase access to activity over the next three years. Additional goals include improving nutrition for 3 million kids; getting 5 million kids outdoors and giving 250,000 children access to nature experiences.

8, 80;: The age span that served as the concept for 8 80 Cities, though they shouldn't be taken literally. “Step one: think of an 8 year old,” explained founder Gil Penalosa, “Step two: think about 80 year old. Step three: ask would they feel safe going to a park? Would you feel comfortable sending them? Stop building cities as if everyone is 30 years old and athletic.”

300: Number of playgrounds opened through the Trust for Public Land's NYC Playgrounds Program by working to open school playgrounds to community use. The example was just one of many ways Penalosa gave attendees to look beyond creating new parks and seeing all public spaces as an opportunity for access to activity. “Become a champion for finding solutions,” he said.

28: Number of finalists for NRPA's Gold Medal Awards, seven of which were announced as winners in their classes. I was quietly rooting for one of Madison's neighbors, the Middleton (Wis.) Public Lands in Class V (population less than 30,000), though they came up short in this year's awards. Congrats to all of this year's winners!