Should You Do Cardio Before Or After Weights?

Finding time during your week to exercise can be enough of a challenge at times, let alone getting the right balance between cardio and strength training. On those days when you want to squeeze in a great workout but suddenly realise how little time you have, it’s normal to wonder - should I do cardio or weights first?

You also might have the same question if you’re someone who has ambitious fitness goals (or a day to yourself and plenty of energy to burn) and you’re looking to smash out some cardio and weight training on the same day.

Although there is some science around how these two different training styles can influence each other when paired together - which we will get into - the key to answering this question is more about knowing what your individual goals are.

Let us explain.

Can you combine cardio with weights?

Absolutely! A combination of cardio and strength training makes for a challenging cross-training workout, which often falls into the category of HIIT (high-intensity interval training) or HIRT (high-intensity resistance training).

This style of workout can be incredibly efficient, effective and a whole lot of fun if you’re looking to boost your cardio fitness and muscular strength at the same time. 

If you’re not familiar with what cardio and strength training means, cardio refers to cardiovascular exercise or aerobic training that elevates your breathing and heart rate, such as running, power-walking, dancing, hiking, cycling, or interval training. Strength training refers to exercises that aim to increase the strength and/or size of your muscles by working against resistance - whether that be the resistance of your bodyweight or added resistance of equipment and gym machines. Both have their unique benefits, are fantastic for your health and should be included in a well-rounded exercise routine.

For those aged between 18 and 64 years, the CDC recommends at least 150 minutes a week of moderate-intensity activity alongside at least two days a week that include strength training exercises.

Programs in the Sweat app that combine cardio and strength training include all of Kayla Itsines’ high-intensity programs, FIERCE with Chontel Duncan, High Intensity Strength with Cass Olholm and HIIT with Monica Jones.

Can you do cardio and weights on the same day? 

If you’re doing cardio and strength training sessions separately, then yes, you can complete them on the same day, but there are a few things you’ll want to take into consideration to ensure you’re looking after yourself and getting the most benefit from your workouts. These may include your goals, energy levels, exercise schedule, rest days and where you’re at in your menstrual cycle.

Cardio or weights first? How to decide

For the most part, deciding whether you do cardio before or after weights should come down to your fitness goals, says the American Council on Exercise, as the order of activity can have an impact on your performance and results. 

If your main goal is to build your cardio fitness… 

Start with cardio. If you start with resistance training, chances are you’ll fatigue your muscles and have minimal muscular power and energy left in the tank for cardio. Following a cardio workout, you could do some strength training with light weights and high reps if you feel up to it, as working on your muscular endurance will complement your cardio goals. 

If your main goal is to gain muscular strength or size…

Start with your weights session to ensure you have maximum energy and muscular power. One 2016 study found average power and velocity were both significantly reduced when resistance exercise followed aerobic endurance exercise, indicating that muscular performance is compromised after cardio. Another study from 2015 produced similar findings, concluding that aerobic exercise before strength exercises impairs your strength performance. 

Getting the most out of your workout isn’t the only reason to start with strength if you’re doing heavy lifting, it also helps to reduce your risk of injury. You're far more likely to hurt yourself or compromise your form when lifting weights if you’re already fatigued or struggling to focus before a strength session.

If you don’t have a specific goal in mind but you want to reap the benefits of both…

A common recommendation is to start with the type of exercise you enjoy the least. This will ensure you get it done and out of the way, while having something to look forward to at the end! You could also try a HIIT program to experience a blend of the two.

If your goal is to lose weight…

Any movement can contribute towards this, so prioritise whatever you enjoy and will stick with long-term! For some people, the endorphin rush of cardio is what keeps them coming back for more, while for others it’s the satisfaction of lifting heavier weights. You do you! 

There is a theory that doing weights first can increase the fat-burning effect of any cardio that follows, while others argue it’s the other way around or suggest prioritising cardio to burn more calories. 

Because evidence is limited and opinions are mixed, we think letting your enjoyment lead the way is the best advice. Losing weight takes time, so our advice here is to focus on exercise that makes you feel great.

If you only want to do a short period of cardio or have limited time…

Make cardio the focus of your warm-up before strength training! A good warm-up is essential to increase blood flow to your muscles and prepare your body for the workout to come, so why not squeeze in your cardio with 5-10 minutes of walking, jogging, rowing, cycling or jumping rope?

If you’re doing two separate sessions in one day… 

Order them according to your energy levels and fitness goals. Schedule the workout that best aligns with your primary goal for when you feel your best. For example, if gaining strength is your focus, you might start your day with weights if that’s when you feel most energetic, or you might perform better in the evening when you’ve eaten and are well-hydrated. See how you feel and find the best time to work out for YOU.

A few other things to consider

If you’re planning on completing two exercise sessions in one day, such as a morning walk to tick off one of your weekly LISS sessions before heading to the gym after work, just remember to listen to your body. More isn’t always a good thing and overtraining is real!

When you’re under a lot of stress, feeling fatigued or your menstrual cycle has got you feeling low, don’t hesitate to dial it back and stick to one session, opt for something gentle like yoga, or have a complete rest day. You’ll feel better about it and come back even stronger.

Structuring your workout schedule can feel like a complicated math equation, especially when you’re juggling the demands of family, study or work, but it doesn’t have to be! 

Should you ever wonder whether to start with cardio or weights, the main thing to ask yourself is, what is my main fitness goal? And then start with the workout that will get you closer to achieving that. If you’re exercising for general health and want a mixture of cardio and strength, finish your workout with the type of exercise you enjoy most, blend the two together, or separate your sessions completely. You’ll be well on your way to reaping the benefits of both!