With the arrival of spring comes race season. This Saturday, the Lynn Woods School Wolf Trot 5K will take place at the reservation of the same name. This is the first time the school is sponsoring the 5K.Lynn Woods is an enjoyable, but challenging, place to run. How big a challenge is it? Well, the race description on Active.com characterizes the loop course as follows: “Wooded hilly area, marked dirt trails.”That is an apt summary of the Woods. Unlike the comforting flatness of a bike path or city street, the undulating surfaces of the reservation pose a test for runners ? especially those going up and down its hills to pass the Steel and Stone Towers during the Lynn Woods summer cross country races.As for the trails, their best description comes from a Bruce Springsteen song: “Rocky Ground.” It is no accident that one such trail is called the Goat Path because it sure helps to be sure-footed!If the Woods presents a challenge, it also represents a sense of calm from running in a natural environment. It may not be the Forest of Arden in Shakespeare’s “As You Like It,” but at 2,200 acres, it is the second-largest municipal park in the US and its tree trunks present a respite from the noise of a highway or city street.With all of this in mind, when you complete a run in the Woods, you may feel exhausted, but chances are you’ll also feel exhilarated.Online registration for the Wolf Trot closed yesterday. However, if you want to run or walk, race day registration starts at 9 a.m. at the Great Woods Road entrance on Saturday. The race itself starts at 11 a.m.The race costs $25 for adults, $10 for students and $60 for a family. There are also free 1-mile and 1K races for “Wolf Cubs.”Springing, and sprinting, into runningThis is an encouraging time of year to pick up, or return to, running. The snow has vanished, save for the occasional mounds piled up in places, and like the robin back from winter vacation, runners are returning to the roads and trails.On recent dog-walks along the North Cambridge bike path with my terrier, Daisy, we have done short sprints on the way back. When I say “short,” I mean it, perhaps 50 yards or even 25. However, it may be the right distance, given that Daisy had problems with her patella (a bone in the knee) this past winter.High-schoolers show fortitudeBy some accounts, Wednesday was a tough day for high school outdoor track teams to run. Bishop Fenwick coach Jay Smith said that his Crusaders both cheered on their teammates and tried to keep warm in their tri-meet with St. Mary’s and Cathedral.As someone who cut short Wednesday’s dog-walk because of the wind, I can only imagine how difficult it must have been to compete that day. Congratulations to all those who did!Rich Tenorio can be reached at [email protected].