A Monday-Sunday Diet Plan to Lose Weight in a Week

Motivation to lose weight can strike any time, and when it does, you need tips you can use immediately (you know, before you get tempted by the ice cream truck or frozen margarita). Whether you're feeling inspired on a Tuesday, Saturday-whenever!-these diet tips for every day of the week practically guarantee success.

Monday: Start Out Strong

Fifty-seven percent of people are guilty of waiting until a Monday to start a diet, research shows. Since motivation is at its peak, set the alarm 45 minutes earlier to hit the gym or go for a run. Bonus: You'll beat the Monday evening crowds when gym attendance soars. Then follow it up with a healthy breakfast, such as Greek yogurt with berries or an egg white and veggie scramble, suggests Larry Cheskin, M.D., director of Johns Hopkins Weight Management Center.

And use Monday as a time to plan for the rest of the week: Look at your calendar for potential diet disasters (business dinners, happy hours, etc.) and decide how you'll tackle them, whether by promising to pass on hors d'oeuvres at your business event, or by packing a snack before happy hour to prevent a booze-fueled pizza run. People who set an action plan in place are more likely to stick to their goals than those who don't, says Linda Illingworth, R.D., director of nutrition services at Lifewellness Institute in San Diego.

Tuesday: Search Smarter

Google queries like—"How to lose weight" and "Healthy dinner ideas"—are 30% higher on Mondays and Tuesdays than any other day of the week, according to a study from San Diego State University. Rather than wasting time sifting through stuff you're not interested in, seek out two or three blogs or websites that inspire you, and subscribe to get weekly emails delivered right to your inbox.

Some sites we love: 101cookbooks.com for veggie-centered meals, fitnessglo.com for workouts you can do at home, and sparkpeople.com for a news, tips, and community of people with similar goals. (But if you're reading food blogs, make sure they're legit. Follow Shape on Instagram and Twitter to get find health, nutrition, and fitness inspiration right in your feed.

Wednesday: Regroup

An ambitious start early in the week can leave you feeling burned out once hump day hits. Use Wednesday to refocus. Make a quick trip to the grocery store to restock on fruits and veggies for the second half of the week. Wednesdays are the least busy day at the supermarket, according to the National Grocer Association, which means shorter lines and produce that hasn't been picked over.

And get on the scale first thing in the morning. For most women, weight peaks on Sunday and bottoms out on Friday, according to research from Cornell University, so weigh in on Wednesday to get a good gage of where you really stand, says lead study author Brian Wansink, Ph.D. People who weigh themselves weekly are better at maintaining weight loss that those who weigh themselves less often.

Thursday: Schedule a Workout

Gym attendance drops drastically after Thursday, according to a study from Johns Hopkins University. Since you're likely to skip out on Friday, getting a sweat session in now is crucial. To make sure you don't flake, plan a standing gym date with a friend, or book your seat at spin or barre in advance (bonus if you have to pay before you go).

Tempted by happy hour? Use a service like Stickk: Promise to go to the gym, and set aside money that will be given to charity if you don't. For an extra nudge, you can select an anti-charity: If you skip the gym, your money will be given to a cause you hate.

Friday: Stick to the Plan

People weigh the least on Friday mornings, research shows, so stick to your plan. The week's not over yet. "Successful dieters stick to their plan 85% of the time and splurge on the weekends," Illingworth says. "If your weekend begins Friday, you're tipping your [indulgences] to more than 40%."

On Friday morning, stick to your usual healthy breakfast and lunch, and then go by this rule at dinner: Choose either the bread basket, a drink, or a dessert.

Saturday: Splurge a Little

People consume 236 more calories on Saturdays compared to any other day of the week, according a study in the journal Obesity. The occasional greasy meal isn't going to kill your diet as long as you don't adopt a to-heck-with-it mentality to overindulge all weekend, Illingworth says. On Saturday, pick one meal to treat yourself: Brunch with girlfriends or the Mexican fiesta- then use your next meal to get back on track.

Sunday: Do Something (Anything!)

If Sundays are your day to plop yourself in a beach chair or on your couch, know this: Physical activity is lowest on Sunday compared to any other day of the week, according to research from Johns Hopkins. Use the day to plan something physical that helps you feel refreshed: A long walk on the beach, a bike ride with a friend, or a few laps in the pool. Think low impact and slow, Illingworth says. A two-hour leisurely stroll in and out of shops can actually burn more calories than a 30-minute run.