As women, we’re often told that High-Intensity Interval Training (HIIT) is the secret to fat loss, energy boosts, and quick, efficient workouts. But the reality is, many of us are missing the mark when it comes to understanding how to truly benefit from HIIT—especially as we enter perimenopause and beyond. Women are generally more metabolically flexible and gravitate towards more endurance workouts, i.e. runs, bootcamps, spinning, because they feel good. However, intensity matters when it comes to HIIT. It should be a few minutes of intense work, around 80-85% of max heart rate with a similar recovery. HIIT workouts shouldn’t last too long otherwise they are categorised at medium intensity and that would defy the entire purpose of that kind of training. Medium intensity workouts will not give you the boost of growth hormone or testosterone you need to build muscle.
Additionally, when you think of fuel partitioning for HIIT, think of it as your body’s method of deciding what energy sources (carbs, fat, protein) to use before, during, and after a workout. This process becomes more crucial as we age and go through hormonal changes like perimenopause, when our bodies become less efficient at burning fat and can lean on muscle breakdown if we don’t manage our nutrition carefully.
Before HIIT: Fuelling Up
The key to a strong HIIT session lies in what you eat before you hit the gym. HIIT relies on quick, explosive movements that use glycogen (stored carbohydrates) as the primary fuel source. If you’re going into a session fasted or with insufficient carbs, your body might burn through muscle to keep up with the high demands.
Research shows that a balanced pre-workout meal consisting of complex carbs and protein—think oatmeal with berries and a scoop of protein—can help preserve muscle and provide sustained energy for those intense bursts. Carbs will fuel your workout, while the protein supports muscle repair. Yes you can eat carbs prior to a workout, even if you are low carb.
After HIIT: The Recovery Window
Post-workout nutrition is equally essential. After a tough HIIT session, your muscles are craving replenishment, and your body needs to refill its glycogen stores. Having protein (20-30 grams) and carbs within 30-60 minutes after your workout is vital to repair muscle and kickstart recovery. For instance, a smoothie with a banana or Greek yogurt with berries and a handful of nuts works wonders for recovery. Avoid the misconception that carbs will “undo” the fat loss benefits—your body needs them for recovery and muscle maintenance, especially as we age.
The 20-30 Minute Limit: Why Less is More in Perimenopause
The common myth with HIIT is that more is better. Most women, especially in perimenopause, aren’t aware that 20-30 minutes is the sweet spot for HIIT. Going beyond that can lead to elevated cortisol levels (the stress hormone), which can sabotage your results by promoting fat storage and muscle breakdown. Women in perimenopause often experience increased cortisol due to fluctuating hormones, making it even more critical to not overdo HIIT. By keeping your sessions short and sharp, you’ll not only burn fat but also keep your body in a state of balance, avoiding excess stress and adrenal burnout.
Another mistake I see often is combining HIIT and strength training in the same workout. While it might feel efficient, this approach can be counterproductive, especially for women in their 40s and beyond. Strength training relies heavily on muscle recovery and glycogen stores, whereas HIIT is about depleting those stores quickly. In perimenopause, recovery takes longer, and combining HIIT with strength can compromise your ability to build and repair muscle. The best strategy is to keep your strength days separate from your HIIT days. Focus on lifting on one day, and reserve your HIIT sessions for a different day to allow your body to maximize benefits from both.
This way, you’re giving each training method the attention it deserves—building strength and improving cardiovascular health without burning out.
Train Smarter, Not Harder
As women, especially those navigating hormonal shifts, we need to understand that HIIT is just one tool in our fitness toolkit. By fuelling properly, limiting your HIIT sessions to 20-30 minutes, and separating your strength and HIIT days, you can create a training plan that works with your body, not against it. HIIT should leave you feeling energized, not depleted. It’s about working smart, not just hard. So, let’s train to support our long-term health, muscle preservation, and overall vitality as we age—because that’s what real strength looks like.