Intermittent fasting has become an increasingly popular diet approach for weight loss and health in recent years. The basic premise involves alternating between periods of fasting and eating, rather than continuous calorie restriction. This appeals to many people as it allows more flexibility with meals and may be easier to stick to long term. But along with diet changes, exercise remains a critical component for achieving fitness goals. So what types of exercise pair best with intermittent fasting? Let’s take a look at the top options.
Benefits of Exercise While Intermittent Fasting
First it’s helpful to understand the key benefits that exercise provides when paired with intermittent fasting:
- Increases calorie burn – Exercise burns additional calories above your basal metabolic rate which enhances calorie deficit from fasting periods.
- Preserves muscle mass – Fasting can cause some loss of muscle if protein intake is low. Strength training counters this effect.
- Boosts metabolism – Weight training in particular helps build metabolism-boosting muscle mass.
- Enhances fitness – Exercise improves cardiovascular health, endurance, strength and flexibility.
- Controls appetite – Physical activity helps regulate ghrelin, the “hunger hormone,” for better appetite control.
- Reduces stress – Exercise provides a healthy outlet for managing stress and anxiety.
Clearly exercise serves as an excellent complement to intermittent fasting on many fronts. But are certain types better suited to pairing with fasting periods?
Ideal Exercise Types for Intermittent Fasting
While any exercise is beneficial, some formats of training sync particularly well with intermittent fasting schedules:
Strength Training
Working with weights checks off several boxes that make it an excellent match for fasting. The major perks are:
- Builds metabolic muscle – Strength training is key for building lean muscle mass which directly correlates to resting metabolic rate. This enhances calories burned both during exercise and at rest.
- Boosts fat burn – Muscle tissue is metabolically active and helps drive fat oxidation. Lifting weights maximizes this effect.
- Prevents muscle loss – Strength training provides resistance to offset potential muscle breakdown during fasting periods.
- Supports bone health – The impact from weight lifting strengthens bones, reducing risk of osteoporosis.
A mix of full body, multi-joint exercises like squats, deadlifts, rows and presses is ideal for gaining muscle. Shoot for at least 2-3 days per week of strength sessions.
HIIT Cardio
High intensity interval training (HIIT) involves short bursts of intense cardio alternated with lower intensity recovery. This type of training jives well with intermittent fasting because:
- Torch calories – The intense effort burns more calories in a short time-frame which works well on fasting days.
- Enhance fat burn – HIIT spikes metabolism and excess post-exercise oxygen consumption leading to greater fat oxidation after the workout.
- Build endurance – Short, hard intervals improve cardiovascular endurance similar to longer steady state cardio.
- Add variety – The quick intense bursts break up monotonous steady state cardio for diversity.
For HIIT, shoot for 20-30 minutes, 3 times per week. Sprints, battling ropes, rowing and cycling are great options.
Yoga
Gentler styles of yoga like Yin and Restorative sync well with fasting for several reasons:
- Lowers stress – Deep breathing and stretching reduce levels of the stress hormone cortisol which tends to run higher when fasting.
- Increases flexibility – Holding passive poses improves joint and muscle flexibility which aids recovery from higher intensity training.
- Calms mind – The meditative nature relaxes the mind and distracts from hunger and food cravings.
- Enhances sleep – Relaxing yoga styles have been shown to improve sleep quality when done in the evening.
Aim for 2-3 yoga sessions per week on non-strength training days. Focus on chest openers, gentle twists and passive hip and hamstring poses.
Low Intensity Steady State Cardio
While HIIT certainly has a metabolic edge for fat burning, easier cardio like walking, cycling and elliptical work still has benefits for fasting including:
- Longer duration burns more total calories which aids the calorie deficit fasting creates.
- Keeps energy levels higher on fasting days compared to being sedentary.
- Provides a break from sitting and mental work which can distract from hunger.
- Carrying lighter conversation is easier during LISS which makes the time pass quickly.
Aim for 30-45 minutes of low intensity cardio 3-4 days per week. This gives the cardiovascular benefits without over-straining the body on calorie restricted fast days.
Exercise Timing with Intermittent Fasting
Along with selecting the right exercise styles, timing your training appropriately around fasting windows will help optimize results.
Training Fasted
Exercising in a fasted state, especially first thing in the morning, has some advantages including:
- Burns fat – With low insulin from fasting, the body more readily draws on fat stores for fuel during training.
- Increases metabolism – A fasted workout triggers a larger post-exercise spike in metabolic rate which turns up the calorie burn.
- Accentuates fat loss – Doing cardio fasted leads to greater fat oxidation during the session.
However, training fasted also comes with some downsides such as low energy, muscle breakdown and over-stressing the body if pushed too hard. So balance and moderation is key.
Training Fed
Exercising in a fed state means having a meal containing protein and carbs 1-2 hours before your workout. Benefits of training fed include:
- More energy – You have readily available blood sugar for fueling intense training.
- Build muscle – Amino acids from pre-workout protein are available to support muscle protein synthesis.
- Better performance – More carbs stored as glycogen in muscles allows higher rep-ranges when lifting.
The downside of training fed is potentially burning a lower ratio of fat calories due to insulin presence from pre-workout carbs. But if your workouts suffer from low energy when training fasted, having a pre-workout meal can be beneficial.
Mixing Fasted and Fed Sessions
A good general guideline is to do lighter, lower intensity cardio sessions when training fasted. Save higher intensity strength training and metabolic conditioning for days when you can eat before exercise. Here is one sample weekly training split:
| Day | Training Type | Fasted or Fed |
|---|---|---|
| Monday | Lower body weights + HIIT sprints | Fed |
| Tuesday | 30 min walk | Fasted |
| Wednesday | Upper body weights + HIIT bike | Fed |
| Thursday | Rest day / stretch | Either |
| Friday | Total body weights + HIIT rowing | Fed |
| Saturday | 60 min low intensity bike | Fasted |
| Sunday | Rest day / stretch | Either |
This splits up the tougher strength and HIIT sessions for fed/post-meal training when you have calories to fuel the demands. The easier fasted cardio days help provide fat burning benefits without overtaxing your body.
Nutrition Recommendations Around Exercise
Along with timing exercise appropriately, fueling nutrients properly around your training is key. Here are some general nutritional guidelines for before and after intermittent fasting workouts:
Pre-Workout
- For high intensity training have a meal 1-2 hours beforehand with lean protein (20-30g), moderate complex carbs (30-60g) and healthy fats.
- Examples: chicken or fish with sweet potato and greens; oatmeal with eggs and nuts; Greek yogurt with berries and granola.
- For lower intensity cardio, BCAAs or EAAs (5-10g) and a little coconut water or fruit juice can provide fast fuel.
Post-Workout
- Have a recovery meal within 60 minutes after training containing 20-40g protein, and carbs to replenish glycogen stores.
- Examples: salmon, quinoa and asparagus; protein shake with banana and nut butter; turkey wrap with avocado.
- Hydrate well with water and electrolytes to rehydrate.
Properly fueling around workouts ensures you recharge and recover optimally from the demands of training.
Sample Training Day
Here is one example of what an ideal training day might look like when paired with a 16:8 style fast:
- 7:00 am – Wake up and drink black coffee or green tea. You’re in a fasted state after sleeping 8+ hours overnight.
- 7:30 am – 60 min fasted cardio workout. For example, go for an outdoor run or use the elliptical machine at the gym.
- 8:30 am – Post-workout, drink a plant protein smoothie. Good opportunity to break your fast with nutrients.
- 10:30 am – Eat a balanced lunch continuing your post-workout nutrition. Aim for lean protein, healthy carbs and fats.
- 1:00 pm – Snack like nuts, veggies and hummus, or fruit to fuel the rest of your workday.
- 4:00 pm – Arrive home from work and have a pre-workout meal, like a turkey sandwich with yogurt.
- 5:30 pm – 60-90 min strength training workout at home or the gym.
- 7:00 pm – Make a healthy dinner with protein, carbs and veggies to refuel from your workout. Seafood, beef or plant meals work great.
- 8:00 pm – Stop eating 2 hours before bed to begin 14+ hour overnight fast until morning.
This schedule takes advantage of fasted cardio in the morning, followed by proper post-workout and daytime nutrition. It fits a hearty pre-workout meal before an evening strength training session. You remain fueled and recover well from two diverse workouts while harmonizing your nutrition with intermittent fasting.
Conclusion
Finding the right training styles and proper timing are critical to maximizing the benefits of exercise with intermittent fasting. Key takeaways include:
- Strength training preserves lean muscle mass and enhances metabolism – aim for 2-3 days/week.
- HIIT cardio provides intense calorie burn in a short duration – shoot for 20-30 min sessions 2-3 days/week.
- Yoga lowers stress and improves recovery between intense training days – try 2-3 sessions per week.
- LISS cardio burns extra calories to aid calorie deficit from fasting – aim for 30-60 min 3-4 days/week.
- Do cardio fasted but have pre-workout meal before weights/HIIT for optimal fueling.
- Support workouts with proper protein and carbs before, during and after.
By following these evidence-based guidelines, you can maximize fat burning and muscle building results from your intermittent fasting plan.
