Impact of Acute Resistance Exercise on Taste Perception and Appetite Response to Plant Protein in Resistance Trained Adults
Condition: Appetite; Taste, Altered; Exercise
MeSH terms: Dysgeusia
Study type: Interventional

Summary: 
      Some evidence suggests that taste perception might be modulated by physical exercise, with
      differences observed after aerobic exercise (DOI:10.1093/chemse/23.4.417) and with habitual
      exercise (DOI:10.3390/nu11010155). However, the effects of resistance exercise on taste
      perception has not been studied. This knowledge is important as it may impact the
      acceptability of foods consumed after exercise.

      While plant-protein supplement powders are gaining increased popularity, their palatability
      and, thereby, acceptability may be a shortcoming. This randomised crossover trial aims to
      investigate (1) the taste perception and acceptability of plant protein supplement powders
      and (2) whether resistance exercise modulates taste perception and appetite responses to
      plant protein.
    

Detailed description: 
      Phase 1 (part 1): A randomised crossover trial, involving 15-20 adult men (aged 18-40 years
      old). Two conditions (resistance exercise or rest) will be undertaken in randomised order.

      Participants will be required to attend three tests visits. The first visit will last
      approximately 2 hours and involves signing informed consent, body composition assessment
      (BodPod), strength tests (3-Repetition Maximum) and completion of questionnaires.

      The second and third visits are the experimental test visits (exercise or rest) and will last
      approximately 4 hours each. Individuals will arrive at the laboratory two hours after
      consuming a standardized breakfast.

      Participants will be provided with eight food-grade samples and asked to complete a battery
      of questionnaires to evaluate taste perception and liking (visual analogue scales (VAS),
      generalised labelled magnitude scale (gLMS), 9-point Likert scale). The eight samples are:
      (1) sucrose (2) umami (3) soy protein (4) pea protein (5) hemp protein (6) brown rice (7)
      whey protein and (8) apple juice. Each sample will be served as a 20-mL-solution. Except for
      sucrose and umami (in water), the protein-based samples will be served in low sugar apple
      juice. Subjects will taste the samples in a "sip-and-spit" manner. Each solution will be
      designated by a 3-digit number and they will be provided in a randomized order.

      Participants will then undergo approximately 1 hour of rest (control) or resistance exercise
      conditions, after which they will repeat an identical tasting session of the 8 samples.

      The resistance exercise will be composed of the 4 exercises, that will be performed at a
      high-to-medium intensity (75% of the maximum calculated), intensity represented by 10
      estimated repetitions. Four sets of each exercise will be assisted by the investigator.

      Phase 1 (part 2): The second part of each test visit (exercise or rest) involves the
      participant consuming a soy protein drink (30g soy protein powder, according to most of the
      manufacturer's recommendation) solubilized in 200ml low-sugar apple juice (to increase
      palatability). After an hour of rest, the participant will then be served an ad libitum lunch
      meal (pasta bake with tomato sauce and cheese, strawberry yogurt and water). Appetite will be
      assessed both during rest and after the lunch meal via VAS.

      Saliva samples will also be collected at three time-points during the test visit to provide
      insight into potential mechanisms contributing to alterations in taste perception and
      appetite.

      Phase 2: Part 1 is extended to 15-20 adult female participants (18-40 years old) to provide
      insight into any potential sex differences in findings. The eight samples tested are
      identical except brown rice protein is replaced with clear protein isolate (a form of
      hydrolysed pea protein).
    

Intervention name(s): Exercise; Rest
Intervention type(s): Other; Other
Intervention description(s): The total volume of exercise is 40 repetitions of each of the 4 exercises. The participant is instructed to perform a maximum of 10 repetitions each set, with 1'30'' rest between sets and between exercises. The researcher provides instructions and verbal encouragement. The total duration of the exercise bout is between 1 hour and 1 hour and 15 minutes.
Part 1: Before and after the exercise condition the participant is sampling 8 different samples: (1) sucrose (2) umami (3) soy protein (4) pea protein (5) hemp protein (6) brown rice (7) whey protein and (8) apple juice.
All protein sources are 3 grams dissolved in 20ml apple juice. Sucrose is 1.66g in 20ml water and umami tastant is 0.09g in 20ml water.
Part 2: a 30g soy protein bolus in 200ml apple juice is given to the participant. After 1 hour energy intake is assessed with an ad libitum lunch meal.; The participant remains in sedentary activities such as reading or using a laptop.
Part 1: Before and after the rest condition the participant is sampling 8 different samples: (1) sucrose (2) umami (3) soy protein (4) pea protein (5) hemp protein (6) brown rice (7) whey protein and (8) apple juice.
All protein sources are 3 grams dissolved in 20ml apple juice. Sucrose is 1.66g in 20ml water and umami tastant is 0.09g in 20ml water.
Part 2: a 30g soy protein bolus in 200ml apple juice is given to the participant. After 1 hour energy intake is assessed with an ad libitum lunch meal.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Other
Keywords: protein; plant protein; soy protein; hemp protein; brown rice protein; pea protein; whey protein; taste perception; taste; appetite; sensory perception; Visual Analogue Scale; Likert Scale; strength training; resistance training