SiS Overnight Protein - 1Kg Tub

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High quality slow release protein that contributes to the maintenance and growth of muscle mass while you sleep:
  • Slowly digested milk protein
  • Maintains muscle mass while you sleep
  • Fuelling gold medal winners since 1992
  • Informed Sport tested

About SiS Overnight Protein

SiS Overnight Protein is made from high quality milk protein for a great taste and trusted source of protein. The product formulation gives a source of slowly digesting protein to give a pool of amino acid to support lean muscle growth and maintenance as you sleep.

Each serving contains 26-27g of protein per serving, depending on the flavour you choose. The milk protein contains the same ratio of fast and slow release proteins as found naturally in milk. Milk protein is over 80% casein, which is a slowly absorbed protein, and around 20% whey, which is rapidly absorbed. Whey protein stimulates the rate of muscle protein synthesis with its' high leucine content. The formulation has low levels of carbohydrate and fat.

Why should I take SiS Overnight Protein?

Sleep is one of the most important aspects of recovery and is often unappreciated by many athletes. Regularly feeding protein every 3-4 hours in servings around 25g is the best way to support the growth and maintenance of lean muscle mass. Feeding during the night is obviously very difficult so taking a slow release protein before bed allows quality sleep and quality protein delivery to maximise your training adaptations.

During times of high volume training it can be difficult to avoid negative energy balance. Taking protein prior to bed reduces the likelihood of lean muscle mass breakdown to supply energy during the night.

Milk protein was recently found to be superior to Micellar Casein in a randomized, double blind trial in supporting resistance training.

As with all SiS products, SiS Whey Protein is produced at our Informed Sport accredited factory and is rigorously screened to ensure a clean, safe product that athletes of all levels trust.

Recommended Usage

SiS Overnight Protein should be taken 45-60 minutes before bed. Can be served hot or cold.

Nutritional Information:

Typical values per serving 35g
  • Energy: 550kj/130kcal
  • Protein: 26g
  • Carbohydrate: 1.9g
  • of which sugars: 0.7g
  • Fat: 2.0g
  • of which saturates: 1.2g
  • Fibre: 1.1g
  • Salt: 0.3g
Contains Milk, Soy - SiS Whey Protein is Gluten Free - Suitable for Vegetarians


Occasionally, without notice, manufacturers change product design and/or specifications.