Getting a second wind
Having energy again, after being tired.
In old English, in the early 14th century, ‘wind’ had the same meaning as ‘breath’. Not much is known about this idiom, but the term came into actual being in the 1800s, when to ‘get a second wind’, was equivalent to being able to take a second breath, or to return to normal breathing after physical exertion.
I thought I was done with my workout but then I had a second wind, and so ran another mile.
We were so tired, we thought we couldn’t walk any further… but then we saw our destination and got a second wind.
I thought I was too tired to finish the race but knowing the finish line was in sight gave me a second wind.