Temperatures and energies were high last month during the 121st running of the Boston Marathon. Over 27,000 runners were transported to the race’s starting line in Hopkinton, all of them with one common goal: to complete a treacherous 26.2 mile journey back to Boston.

By the time all runners had officially started the race, temperatures had climbed into the low 70s, a significant increase from the week’s earlier forecasts. Passing cloud cover and a consistent tailwind stood as the only relief from an otherwise challenging set of race conditions.

However, runners were never at a loss for inspiration as they entered their starting corrals. Kathryn Switzer, the first woman to finish the Boston Marathon as a numbered entry, returned to the race to deliver the starting command for the elite women. Switzer, 70, then completed the race herself — it was the first time she had done so since she was nearly pulled off the course by a race official in 1967.

Meanwhile, the male elite pool was highlighted by Meb Keflezighi, whose announcement alone sent passionate shockwaves through the faster corral groups. A former olympic silver medalist, Keflezighi is the only American to win the marathon since 1983 — and he did so in iconic fashion, one year after the tragic Boston Marathon bombing. Keflezighi announced the race would be his last competitive appearance at Boston.

Per usual, race spectators exhibited a seemingly endless supply of energy. This support proved to be an asset to runners, as the Boston course is a dangerous seductress of sorts; it begins with a cumulative drop of nearly 300 feet during its opening 10k. Then, the course levels off into rolling terrain until mile 16, when runners enter the town of Newton and are faced with a series of challenging hills (the last of which being the infamous “Heartbreak Hill,” a grueling 600 meter incline between miles 20 and 21).

Each year, many participants make the mistake of running the race’s opening miles too quickly, only to be crushed by the Newton hills. This year, crowds at these hills seemed hell bent on displacing potential disappointment with overwhelming motivation, with many of them offering additional water stations and other means of energy replenishment to combat the added stress of the heat.

Around 97 percent of runners defied the conditions and finished the race. Among the finishers was Jose Luis Sanchez, a former marine who lost part of his leg while serving in Afghanistan. Sanchez ran the entire marathon carrying an American flag.

On the elite end, Edna Kiplagat and Geoffery Kurui were the race’s male and female champions, respectively. Galen Rupp and Jordan Hasay finished as the top American runners (Rupp was second and Hasay was third).