Impact of Acute Resistance Exercise on Taste Perception and Appetite Response to Plant Protein in Resistance Trained Adults

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.

Study Overview

• Status: Completed
• Conditions: Exercise; Taste, Altered; Appetite
• Intervention / Treatment: Other: Exercise; Other: Rest

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).

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Ireland
  • Dublin, Ireland
    • University College Dublin

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Phase 1: Adult males; Phase 2: Adult females
• Aged between 18 and 40 y.o.)
• Physically active in accordance with IPAQ
• Lifting weights, at least, once a week
• Healthy
• Non-smokers
• BMI between 18 and 30

Exclusion Criteria:

• Phase 1: Females; Phase 2: Males
• Subjects younger than 18 or older than 40 y.o.
• BMI lower than 18 and higher than 30
• Insufficiently active individuals
• Physical active individuals that do not perform a regular strength training
• Having any condition health-related that could preclude both their participation in physical testing and a bout of resistance training
• Taking medications known to impact taste and/or appetite
• Medical condition known to impact taste and/or appetite
• Medical condition linked to cognitive impairment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Exercise; Resistance exercise involves 4 exercises (bench pull, bench press, leg extension and unilateral leg press), that are performed at 75% of maximum, determined from 3-RM test.	Other: Exercise; 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.
Experimental: Rest; One hour rest.	Other: Rest; 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: Change in Taste Intensity	Taste intensity from Generalised Labelled Magnitude Scale (gLMS) Validated 200 millimetre scales will be used to assess intensity of the taste of each sample. This scale has anchors located at each end of the scale and along the scale (barely detectable, weak, moderate, strong, very strong, strongest imaginable). On the bottom end of the scale, the extreme negative response (0 mm) is represented, while the top end (200 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest).
Part 1: Change in Liking of the samples	9-point Likert Scale to rate overall liking of each sample, from 0 (dislike extremely) to 9 (like extremely).	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest). Change scores will be compared between exercise and rest condition.
Part 2: Change in Appetite - Composite Appetite Score	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to assess appetite, at six (6) set time points throughout the experimental visit. This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Composite Appetite Score derived from aspects such as hunger, fullness, desire to eat and prospective food consumption will be calculated.	3.5 hours: (1) at participant arrival, (2) after exercise or resting condition (3) immediately after the protein bolus (4) 30 minutes after the protein bolus (5) 60 minutes after the protein bolus (6) after the lunch meal
Part 2: Energy Intake	Energy intake measurement. Participants will be given a standardised fixed breakfast to be eaten at home 2 hours prior the testing visit. At the end of the testing visit participants will be served with ad libitum lunch meal in the laboratory. Lunch EI (kilocalories) will be measured objectively, by weighing foods before and after consumption and calculating energy intake based on their nutritional data. EI will be compared between exercise and rest conditions	Day 2 and Day 3

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 2: changes in cortisol	Saliva sample will be collected by passive drooling three (3) times.	3 hours: (1) immediately after participant arrival, (2) after exercise or rest, (3) 1 hour after exercise or rest (i.e. immediately before the lunch meal)
Part 2: changes in testosterone	Saliva sample will be collected by passive drooling three (3) times.	3 hours: (1) immediately after participant arrival, (2) after exercise or rest, (3) 1 hour after exercise or rest (i.e. immediately before the lunch meal)
Part 2: Palatability - Pleasantness	100 millimetre Visual Analogue Scales (VAS) will be used immediately after the protein bolus and the lunch meal. This VAS has anchors located at each end of the scale. On the left end of the scale (0 mm), the extreme negative response is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Data will be compared between exercise and rest conditions.	Day 2 and Day 3
Part 2: Palatability - Filling	100 millimetre Visual Analogue Scales (VAS) will be used immediately after the protein bolus and the lunch meal. This VAS has anchors located at each end of the scale. On the left end of the scale (0 mm), the extreme negative response is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Data will be compared between exercise and rest conditions.	Day 2 and Day 3
Part 2: Palatability - Satisfaction	100 millimetre Visual Analogue Scales (VAS) will be used immediately after the protein bolus and the lunch meal. This VAS has anchors located at each end of the scale. On the left end of the scale (0 mm), the extreme negative response is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Data will be compared between exercise and rest conditions.	Day 2 and Day 3
Part 2: Palatability - Taste	100 millimetre Visual Analogue Scales (VAS) will be used immediately after the protein bolus and the lunch meal. This VAS has anchors located at each end of the scale. On the left end of the scale (0 mm), the extreme negative response is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Data will be compared between exercise and rest conditions.	Day 2 and Day 3
Part 2: Palatability - Sweet	100 millimetre Visual Analogue Scales (VAS) will be used immediately after the protein bolus and the lunch meal. This VAS has anchors located at each end of the scale. On the left end of the scale (0 mm), the extreme negative response is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Data will be compared between exercise and rest conditions.	Day 2 and Day 3
Part 2: Palatability - Savoury	100 millimetre Visual Analogue Scales (VAS) will be used immediately after the protein bolus and the lunch meal. This VAS has anchors located at each end of the scale. On the left end of the scale (0 mm), the extreme negative response is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Data will be compared between exercise and rest conditions.	Day 2 and Day 3
Part 2: Changes in Hunger	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to estimate changes in appetite, at six (6) set time points throughout the experimental visit. This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Data will be compared between exercise and rest conditions.	3.5 hours: (1) at participant arrival, (2) after exercise or resting condition (3) immediately after the protein bolus (4) 30 minutes after the protein bolus (5) 60 minutes after the protein bolus (6) after lunch. Mixed model ANOVA will be used.
Part 2: Changes in Fullness	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to estimate changes in appetite, at six (6) set time points throughout the experimental visit. This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Data will be compared between exercise and rest conditions.	3.5 hours: (1) at participant arrival, (2) after exercise or resting condition (3) immediately after the protein bolus (4) 30 minutes after the protein bolus (5) 60 minutes after the protein bolus (6) after lunch. Mixed model ANOVA will be used.
Part 2: Changes in Desire to Eat	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to estimate changes in appetite, at six (6) set time points throughout the experimental visit. This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Data will be compared between exercise and rest conditions.	3.5 hours: (1) at participant arrival, (2) after exercise or resting condition (3) immediately after the protein bolus (4) 30 minutes after the protein bolus (5) 60 minutes after the protein bolus (6) after lunch. Mixed model ANOVA will be used.
Part 2: Changes in Prospective Food Consumption	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to estimate changes in appetite, at six (6) set time points throughout the experimental visit. This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Data will be compared between exercise and rest conditions.	3.5 hours: (1) at participant arrival, (2) after exercise or resting condition (3) immediately after the protein bolus (4) 30 minutes after the protein bolus (5) 60 minutes after the protein bolus (6) after lunch. Mixed model ANOVA will be used.
Part 1: Changes in Sensory Perception - Visual Appeal	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to assess sensory perception during two sampling session (8 times each sampling session). This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends. Change scores will be compared between exercise and rest conditions.	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest)
Part 1: Changes in Sensory Perception - Smell	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to assess sensory perception during two sampling session (8 times each sampling session). This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Change scores will be compared between exercise and rest conditions.	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest)
Part 1: Changes in Sensory Perception - Taste	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to assess sensory perception during two sampling session (8 times each sampling session). This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Change scores will be compared between exercise and rest conditions.	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest)
Part 1: changes in Sensory Perception - Aftertaste	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to assess sensory perception during two sampling session (8 times each sampling session). This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Change scores will be compared between exercise and rest conditions.	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest)
Part 1: Changes in Sensory Perception - Palatability	Validated 100 millimetre Visual Analogue Scales (VAS) will be used to assess sensory perception during two sampling session (8 times each sampling session). This VAS has anchors located at each end of the scale. On the left end of the scale, the extreme negative response (0 mm) is represented, while the right end (100 mm) represents the positive response. Participants mark along the line where it most represents their subjective perception between both ends.Change scores will be compared between exercise and rest conditions.	2 hours: (1) baseline sampling session, (2) post-intervention sampling session (i.e. after 1 hour resistance training or rest)

Collaborators and Investigators

• Sponsor: University College Dublin

Study record dates

Study Major Dates

• Study Start (Actual): August 8, 2022
• Primary Completion (Actual): May 19, 2023
• Study Completion (Actual): May 19, 2023

Study Registration Dates

• First Submitted: March 13, 2023
• First Submitted That Met QC Criteria: October 11, 2023
• First Posted (Actual): October 19, 2023

Study Record Updates

• Last Update Posted (Actual): October 19, 2023
• Last Update Submitted That Met QC Criteria: October 11, 2023
• Last Verified: October 1, 2023

More Information

Terms related to this study

• Keywords: appetite; strength training; soy protein; whey protein; resistance training; plant protein; protein; Visual Analogue Scale; taste; taste perception; pea protein; sensory perception; hemp protein; brown rice protein; Likert Scale
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Sensation Disorders; Taste Disorders; Dysgeusia
• Other Study ID Numbers: LS-22-30-Horner

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No