Exercise is one of the most powerful tools we have for mood, strength, sleep, metabolism, and disease prevention. But knowing that exercise is good for us is very different from knowing how to start. The best exercise program is not the most complex one. It is the one you can do safely, consistently, for years.
Whether you are young or old, thin or overweight, athletic or deconditioned, the first principle is the same: start where you are, not where you think you “should” be. Thin does not always mean fit. Overweight does not mean incapable. Older does not mean too late. The body adapts at every age when the dose is appropriate.
The Four Pillars of a Good Exercise Program
1. Aerobic fitness: This includes walking, cycling, swimming, jogging, rowing, hiking, dancing, or any activity that raises your heart rate. For general health, adults should aim for at least 150 minutes per week of moderate-intensity activity, such as brisk walking, or 75 minutes per week of more vigorous activity, plus strength training at least two days weekly. More benefit generally occurs as people build toward 300 minutes per week (1).
2. Strength training: Muscle is not just for appearance. It protects joints, improves insulin sensitivity, preserves function, supports bone health, and becomes increasingly important with age. Train all major muscle groups at least twice weekly: legs, hips, back, chest, shoulders, arms, and core. Bodyweight, resistance bands, machines, dumbbells, kettlebells, and barbells can all work. ACSM’s 2026 resistance-training update emphasizes that consistency matters more than chasing a “perfect” program; for muscle growth, a useful target is roughly 4-10 weekly sets per muscle group, adjusted to goals, ability and recovery (2).
3. Mobility and balance: Mobility helps you move well; balance helps you stay independent. This is important for all ages, but especially important for older adults, who should include balance work along with aerobic and strengthening activity. Examples include heel-to-toe walking, single-leg stands, tai chi, yoga, controlled lunges, step-ups, or simply practicing getting up and down from a chair (3).
4. Recovery: Fitness is not built only during the workout. It is built when the body repairs and adapts afterward. Recovery means adequate sleep, hydration, nutrition, easier days between harder days, and listening to pain signals. Soreness can be normal; sharp pain, swelling, chest pain, fainting, or worsening symptoms are not.
How Much Time Is Needed?
One of the main questions that people often have is: How long do I have to work out? And the answer is: it depends on what you are doing.
For longevity and general health, a realistic goal is 30 minutes of moderate activity five days per week, plus two short strength sessions. This can be broken into smaller chunks; ten minutes at a time still counts.
For weight loss or weight maintenance, exercise helps, but nutrition matters greatly. Many people need higher activity levels, often closer to 300 minutes per week, along with dietary changes, to lose weight or keep it off. Low-impact choices such as walking, cycling, swimming, elliptical, or water exercise are often good starting points for people with joint pain or significant excess weight (4).
For aerobic events (running, cycling etc.) first build consistency, then duration, then intensity. Beginners should spend most sessions at an easy “conversation pace.” New runners often do best with run-walk intervals. A practical injury-reduction rule is to increase running mileage gradually, commonly by no more than about 10% per week (5).
For building muscle, train each major muscle group about two to three times per week. Start with one to three sets per exercise, learn good technique, and progress slowly. You do not need to destroy yourself. You need repeated, progressive effort over months and years.
How to Reduce Injury Risk
A popular excuse that people give for not working out is that they are afraid that if they work out more they risk getting injured. However, most injuries come from doing too much, too soon, too often, with too little recovery.
some things that will help with longevity and injury prevention while working out are:
Increase only one thing at a time — duration, intensity, frequency, or load. Do not increase all four at once.
Warm up for 5–10 minutes with an easier version of the activity you are about to do. Cool down gradually afterward. This helps the cardiovascular system and muscles transition safely into and out of exercise (6).
Pain is information. Mild muscle soreness is common. Joint pain, limping, sharp pain, chest pressure, unusual shortness of breath, dizziness, or symptoms that worsen during exercise should be taken seriously. People with known heart disease, uncontrolled blood pressure, diabetes complications, significant orthopedic problems, pregnancy-related concerns, or major chronic disease should discuss an appropriate plan with a healthcare professional (7).
Always Make It Enjoyable
Discipline helps, but enjoyment wins long-term.
Pick activities you actually like, or at least do not hate. Walk with a friend. Listen to music, podcasts, or audiobooks. Join a class. Play pickleball, tennis, basketball, golf, or dance. Ride outdoors. Hike. Make it social. Make it scenic. Make it a break from stress rather than another punishment.
Use habit stacking: attach exercise to something you already do.
After morning coffee, walk for 10 minutes.
After work, change immediately into workout clothes.
After dinner, take a family walk.
Before showering, or before or after meals, do one set of push-ups, squats, or resistance-band rows.
Use rewards wisely. The reward should reinforce the identity: “I am someone who moves.” Track workouts on a calendar. Celebrate streaks. Buy comfortable shoes. Save a favorite podcast for walks. Meet a friend afterward. The goal is to make the behavior satisfying enough that you want to repeat it.
Consider Tart Cherry Juice, magnesium, sulforaphane, or well-sourced omega-3 fatty acids to support recovery, and curcumin to limit inflammation; consume creatine monohydrate and caffeine to support cellular energy and power; add protein powder or BCAA for recovery and growth.
Start Small, Then Build
The person who walks 10 minutes a day is doing far better than the person waiting for the perfect 90- minute program. Start with what feels almost too easy. Build confidence. Add time. Add strength. Add
intensity later.
The long-term goal is not a 6-week transformation. It is becoming the kind of person who moves daily, lifts regularly, recovers intentionally, and enjoys the process.
Exercise is medicine — but the best dose is the one you can keep taking.
Thanks for taking care of your human.
Warmly,
Martin Katz, MD
This letter is for educational purposes only and is not a substitute for personal medical advice.
1. https://www.cdc.gov/physical-activity-basics/guidelines/adults.html
2. https://acsm.org/resistance-training-guidelines-update-2026/
3. https://www.cdc.gov/physical-activity-basics/guidelines/older-adults.html
4. https://www.niddk.nih.gov/health-information/weight-management/tips-get-active/tips-starting-physical activity
5. https://www.mayoclinichealthsystem.org/hometown-health/speaking-of-health/how-can-i-become-a better-runner-and-avoid-injury
6. https://www.heart.org/en/healthy-living/exercise-and-physical-activity/fitness-basics/warm-up-cool down
7. https://www.cdc.gov/healthy-weight-growth/physical-activity/getting-started.html
