8 Fitness Challenges Worth Trying (and How to Do Them Safely)

A fitness challenge gives a vague goal (“get fitter”) a clear shape: one activity, a set number of days, and a way to see progress. That structure is what makes challenges useful. The risk is the opposite problem: doing too much too soon. This guide covers eight challenges that suit most healthy adults, how to set each one up, and how to scale it so it builds a habit instead of an injury.

Before you start: if you have a heart condition, high blood pressure, joint problems, are pregnant, or haven’t exercised in a long time, check with a doctor first. Stop any exercise that causes chest pain, dizziness, or sharp joint pain.

Start with the baseline: how much activity adults need

The CDC’s guidance for adults is at least 150 minutes a week of moderate-intensity activity (such as brisk walking), plus muscle-strengthening activity that works all major muscle groups on at least two days a week. A good challenge either helps you reach that baseline or builds on top of it. If you’re currently doing very little, the walking and “minutes” challenges below are the best place to start.

1. The daily walk challenge

The idea: walk every day for 30 days. Start with whatever is comfortable, even 10 minutes, and add a few minutes each week until most days reach 20–30 minutes at a pace where you can talk but not sing.

Why it works: walking needs no equipment, is low impact, and five 30-minute brisk walks add up to the 150-minute weekly baseline on their own.

Track it: minutes walked per day, in a notes app or on a paper calendar.

2. The couch-to-5K challenge

The idea: go from not running to running 5 km (about 3.1 miles) using a structured run/walk plan. The NHS Couch to 5K programme is free and spreads this over nine weeks, with three short sessions a week that gradually shift from mostly walking to continuous running.

Scale it: it’s fine to repeat a week if it felt too hard. Rest days between runs matter; they’re when your body adapts.

3. The plank challenge

The idea: hold a plank daily and slowly extend the time. A plank works the deep core muscles along with the shoulders and glutes.

• Forearms under shoulders, body in a straight line from head to heels.
• Brace your stomach and squeeze your glutes; don’t let the hips sag or pike up.
• Start with what you can hold with good form, even 15–20 seconds, and add 5–10 seconds every few days.
• Too hard? Drop to your knees (a modified plank) and keep the same straight line from head to knees.

Form matters more than time. Ending the set when your hips start to drop is better than holding a sagging plank for longer.

4. The squat or push-up progression

The idea: pick one bodyweight exercise and add a few reps per session over 30 days. This counts toward the two days of muscle strengthening in the CDC guidance.

• Squats: feet about shoulder-width apart, sit back as if into a chair, knees tracking over the toes. Use a real chair to tap down onto if you need a depth guide.
• Push-ups: start against a wall or kitchen counter, then move to knees, then full push-ups as you get stronger.

Train every other day rather than daily, so the muscles have time to recover.

5. The burpee challenge (for people who already train)

The idea: a set number of burpees a day, increasing slowly. Burpees combine a squat, a plank, and a jump, so they raise the heart rate quickly. They’re also hard on wrists, shoulders, and knees, which is why this one suits people with an existing exercise habit.

Scale it: step back instead of jumping back, skip the push-up, and replace the jump with a rise onto your toes. Quality reps beat a big daily number.

6. The 30-day stretching challenge

The idea: 10 minutes of stretching every day, covering the hips, hamstrings, calves, chest, and shoulders. Mayo Clinic’s guidance is to stretch muscles once they’re warm, hold each stretch without bouncing, and stretch to the point of mild tension, not pain.

This one pairs well with any of the other challenges: do it after your walk or strength session.

7. The “half-plate vegetables” nutrition challenge

The idea: instead of a strict diet, change one habit for a month. A simple, evidence-based one is the USDA MyPlate pattern: make half your plate fruits and vegetables at most meals.

• Pick one meal a day to start with, usually lunch or dinner.
• Swap sugary drinks for water as a second habit once the first feels easy.
• Avoid challenges built on extreme calorie cuts or cutting out whole food groups. If you have a medical condition or a history of disordered eating, talk to a doctor or registered dietitian before changing how you eat.

8. The personal-best challenge

The idea: test one measure on day 1 (a timed 1-mile walk, max push-ups with good form, a plank hold) and retest on day 30. Train normally in between. This turns any of the challenges above into something you can measure, and competing with your own last result is more useful than comparing yourself with other people.

How to make a challenge stick

• Pick one challenge at a time. Stacking three new habits in the same month is the most common reason people quit.
• Start below your limit. The first week should feel easy. Progress comes from showing up, not from a hard day 1.
• Write it down. A calendar with a tick for each day is enough.
• Plan rest. Strength and running challenges need recovery days; walking and stretching can be daily.
• Do it with someone. A friend, family member, or online group adds accountability.

Related reading

• 5 Ways to Stay Motivated and Achieve Your Fitness Goals
• How to Use Resistance Bands: Full-Body Exercises and Benefits
• Top 10 Workout Programs for Seniors