Supplementing with post-workout protein brings no significant benefits in LOW-HIIT setting, study finds

22 Sep 2022 --- New scientific evidence indicates that individuals who consume protein after participating in low-volume high-intensity interval training (LOW-HIIT) are not actually reaping any significant benefits from this supplementation. The study was undertaken at the Friedrich-Alexander University Erlangen-Nürnberg, in Germany.

There is ample evidence that specific nutritional strategies can enhance people’s physical adaptability to resistance and endurance training. It has been reported, for example, that there is evidence to suggest that several supplements, including sodium bicarbonate, nitrates, beta-alanine, caffeine and creatine, may provide potential benefits for improving HIIT adaptations.

The potential of certain nutritional strategies or specific supplements taken after LOW-HIIT is still relatively sparsely investigated.However, in contrast, the potential of certain nutritional strategies or specific supplements taken after LOW-HIIT is still relatively sparsely investigated. 

“To the best of our knowledge, the present study was the first to investigate the influence of a targeted post-session protein supplementation on physiological adaptations to LOW-HIIT in a cohort of previously sedentary individuals,” the study authors report.

No evidence of post-workout supplementation benefit
LOW-HIIT generally appeals to time-starved consumers, due to convenience and the lower amount of effort required to participate in this activity, compared to more intensive sports.

As part of the study, 47 middle-aged participants performed cycle ergometer LOW-HIIT for eight weeks and randomly received either double-blinded 40 g of whey protein or an isocaloric placebo – maltodextrin – after each session.

There were no significant between-group differences in any of the outcome changes.

The maximum oxygen uptake and several secondary cardiometabolic outcomes were determined both pre and post-intervention. This value increased in both the PRO-HIIT group and the placebo group (PLA-HIIT).

Systolic and diastolic blood pressure also decreased at a similar rate in both PRO-HIIT and PLA-HIIT groups. Meanwhile, gamma glutamyl transferase decreased in PRO-HIIT and alanine aminotransferase in PLA-HIIT.

Overall, the researchers conclude that LOW-HIIT improved the oxygen uptake and other cardiometabolic markers, irrespective of the supplementation condition.

“Post-session protein supplementation does not seem to provide any additional benefit to LOW-HIIT in improving cardiometabolic health in sedentary healthy individuals,” they remark.

“The practical take-home message from this study is that individuals who consume adequate amounts of protein in their daily diet (i.e., ≥1.0 g/kg) do not seem to specifically benefit from ingesting a protein supplement after a session of LOW-HIIT.”

Statistical differences in higher-volume training
Previous research on the significance of proper protein intake is mainly based on studies using resistance training regimes, but it has also been documented that the consumption of a high-quality protein in doses of 20-40 g after a session of higher-volume endurance training may maximize muscle protein synthesis and support recovery processes.

However, given that most of the previous studies investigating the effects of protein supplements in conjunction with endurance training have typically used higher exercise volumes, there is currently still a lack of data on whether individuals engaged in LOW-HIIT may also benefit from a targeted post-session protein supplementation.

“Given the constantly high popularity of (LOW-)HIIT in recent years, it appears timely to address this research gap,” note the Friedrich-Alexander researchers.

The majority of participants stated that they enjoyed engaging in LOW-HIIT. On a 7-point rating scale (1 = not enjoyable at all, and 7 = extremely enjoyable) the exercise program was rated with an average score of 5.7 ± 1.0 and 88% of participants reported that they intend to continue with LOW-HIIT on their own after the termination of the study.

The popularity of post-workout supplementation has prompted related launches, such as Lactalis’ recently unveiled whey protein offerings, branded UP2U Recover, which is being marketed as the “purest form” of whey protein, also known as “native” protein powder.

In other developments, whey protein items are becoming increasingly specialized, with companies optimizing the taste performance and a link with increased immunity. 

By Benjamin Ferrer