Domenica Ramos immigrated to New York City from Ecuador in 2001. In 2013, she started starting running to cope with the stress of single motherhood and quickly became a Boston Marathon qualifier, finishing her fourth marathon last month in Chicago with a time of 3 hours 24 minutes 12 seconds. A resident of Hamilton Heights in Manhattan, Ms. Ramos, 33, balances training with 12-hour waitressing shifts and caring for her 6-year-old daughter, Gabriela. She was hoping to finish the New York City Marathon in 3 hours 20 minutes. Recently, however, a mild injury flared up, threatening to slow Ms. Ramos down, but not stop her: “Deeply in my heart,” she said, “I want to line up at the start and run this marathon.”

BEAT THE SUN Sunday is the only day with my daughter so I need to run early. I get home from work at 11:30 the night before, but I’m used to it and I wake up at 4:45 a.m. I drink water and have a banana and a peanut butter sandwich. I get dressed quickly and run to the train station.

SUBWAY STRETCH I take the 1 train to either Central Park or Van Cortlandt Park, in the Bronx. I stretch on the train; I look like a crazy person. I meet my friends Marines, from the Dominican Republic, and Alberto, who is from Ecuador, too. He makes the plans, runs with me, corrects my form, teaches me how to pace. I met him through my team, the West Side Runners. He treats us like a family. Alberto coaches us for free, because he says we are into the sport. There’s no joking around, and we are getting good results with him.

NO TALKING We start running right away, by 5:30 a.m. Sundays are long runs. We start with a slow pace, then for the rest of it, we run faster, and there is no talk. You just concentrate on running so it becomes easier.

WARDROBE CHANGE Once we finish, we stretch and change into clothes that we carried with us on the run in backpacks. When I began running I used to get sick because I didn’t know you had to change.

TIME FOR A SHOCK I am home by 8. To recover, I sit in my bathtub for an ice bath, letting the cold water run on me, and then I add the ice. The first time I did it, it was horrible, I made the mistake of putting the ice in the water before I got in. I was shocked. I thought, how could someone do this? Then I’ll go to sleep, minimum 30 minutes, maximum two hours. If I didn’t take her in the running stroller, whoever’s watching my daughter wakes me up — usually my sister or a babysitter or her father.

SLITHERY, SLIMY THINGS I spend the rest of the day with my daughter. She loves animals, so she often picks the Bronx Zoo. She is always so excited, like it’s the first time. I’ve prepared everything we need the night before, so I don’t waste time or worry about anything, and we are ready to leave right away, around noon. She loves reptiles, so we have to go see the reptiles first. I love being with her and seeing her happy.

SISTER LOVE Then we go to my sister’s boyfriend’s restaurant, Arco Cafe, on Amsterdam and 103rd. We get there around 5 or 6, for dinner. It’s the only time I get to see my sister — she is a waitress — unless she’s helping me in the morning. We came to New York together, and she’s my family here; we haven’t seen our mother since 2001. My sister incentivized me to run. I was stressed out, everything was so difficult: the child, the work, managing everything, and she told me to run because it might help me think better. It helped me a lot.

BEDTIME FOR LITTLE COACH We come home, brush our teeth, read a book and go to bed by 9 at the latest. Gabriela has National Geographic encyclopedias, and she always picks an animal to read about. She usually picks cheetahs; they’re the fastest and she says she’s a cheetah. When I bring her in the stroller, she’s always telling us: “Faster! Too slow!” The guys call her “little coach.”

UNPACKING THE RUN When the light goes off, I’m out. But I try to think about running before, maybe how I made mistakes in training, trying to correct them. Sometimes I’m too hard on myself, with running, but it helps me to deal with stress, to find the positive side of the problem. Running helps you to keep getting better.