I don’t always take a rest day, but when I do it’s to give the weights a break, not me.

Rest days are a widely debated topic in the fitness industry, we all know we need rest in order to recover but how do you properly rest? Can you do cardio on your rest days without halting your progress? This is never going to be a clear cut yes/no answer, as people train for all different reasons and no two bodies will react the same to training. Typically people train with two main purposes, gain muscle or lose weight and, therefore, these are the most widely researched areas when it comes to cardio on rest days.

Cardio on Rest Days

Scenario 1:

Should I do cardio on my rest days if I’m trying to build muscle?

When trying to build muscle, lifting days involve intense training, heavy compound lifts stress the muscles causing micro tears and it is on rest days that the body adapts to compensate for the stresses put on your body through training, repairing these muscle tears so the muscles grow stronger and increase their work capacity. Without adequate recovery, there will be no signs of growth or strength. This suggests that for hard gainers to succeed rest day cardio would be detrimental, as although it is working the muscles differently, cardio still takes energy from the same muscles you are trying to recover, thus resulting in hindered progress. However, low intensity exercise can help increase blood flow to tired muscles, enhancing recovery without impeding muscle gains, such as a long walk or yoga session.

Research in The Journal of Strength and Conditioning compared cycling with incline walking on a treadmill and found that cycling was significantly better for achieving hypertrophy when combined with resistance training compared to incline treadmill walking, suggesting if you are going to do gym-based cardio on your rest days, keep it low impact to reap the cardiovascular rewards and keep it on a bike to preserve muscular gains.

Top Tip:  Keep your heart rate between 100 and 130 beats per minute and no higher than zone 2 to avoid slowing down your recovery.

Scenario 2:

Should I do cardio on my rest days if I’m trying to lose weight?

In this scenario, the purpose of creating more muscle is to burn more fat. The more muscle we have the more calories we burn at rest. When trying to lose weight the key factor is to create a calorie deficit, resulting in weight loss. On rest days light cardio would enable fat loss through the additional calorie deficit without going catabolic through high intensity. The problem with this is that consistent restrictive dieting and resistance training takes a huge toll on your body and over training can be counterproductive, as your body begins to lose the muscle you’ve been trying to gain and never has a chance to recuperate from exercise, which in turn damages your metabolism. A calorie deficit can be maintained through diet on rest days in order to stay on track and avoid overtraining. If however you do want to train, stick with lower intensity activities within your zone 2 heart rate capacity (as with the above) in order to allow for recovery. Swimming is a great form of lower intensity exercise as it allows training without putting any strain on the joints.

Signs of Overtraining:

If you experience signs of overtraining, it’s time to take some well earned complete rest days, from cardio and weights alike. Signs of overtraining include:

  • Headaches
  • Insomnia/Sleep Problems
  • Lack of motivation
  • Constantly feeling fatigued and lacking energy
  • General body aches or mild muscle soreness
  • Decrease in performance
  • Inability to complete workouts
  • Increases susceptibility to infections
  • Persistent tiredness
  • Irritability
  • Mental Breakdown

With cardio on rest days, it’s very difficult to create a definitive answer. The best advice is to listen to your body and find what works best for you.