Intervention：

Study 1 recruited 10 male fitness enthusiasts from Beijing Sport University, aged 18-24 years old. Before the intervention, health examination was carried out to eliminate disturbing factors. The age, sex, medical history, health status, physical activity level and daily diet of the subjects were investigated by questionnaire, and informed consent was signed. The subjects were randomly divided into whey protein group (group W, n=5) and control group (group C, n=5) in a randomized cross-over double-blind experiment. After one intervention, group W and group C exchanged supplements for another intervention, during which they were eluted for 7 days. The action mode of acute resistance exercise is squat and bench press with barbell. Subjects were asked to squat at the same level as the femoral trochanter and knee joint, then fully extend the knee, bench press subjects were asked to drop the bar to touch the upper chest, and lift the elbow joint fully straight. The exercise training load follows the guidelines established by the American Strength and Conditioning Association, and a 1RM test is performed prior to the intervention in order to determine the intensity of the intervention in subsequent subjects. The specific training plan is as follows: ① Preparation activity: Repeat the 50% 1RM squat and bench press 8-10 times each, then rest for 60 s. ② The order of resistance exercise is to complete the squat first and then the bench press. The first 4 groups of squat load was 70% 1RM, each group repeated 8 times, rest between groups 60s; After the completion of the fourth group, rest 90s, and then complete the four sets of squat with a load of 50% 1RM. The first and second groups are repeated 8 times each, and the third and fourth groups are repeated until they cannot be completed (if the third group is exhausted, there is no need to do the fourth group). The rest between the groups is 60 s, and the fourth group is finished with a rest of 150 s. Then the movement was changed, and the load was 70% 1RM bench press 4 groups, each group repeated 8 times, and the rest between the groups was 60 s; After the completion of group 4, rest for 90 s, and then complete the bench press 4 sets at 50% 1RM, and repeat 8 times in groups 1 and 2, and repeat in groups 3 and 4 until they cannot be completed (if group 3 is exhausted, do not do group 4). In addition, the nutritional supplement program was as follows: Group W supplemented 1 bottle of Pinku protein product (300ml) 1 hour before and immediately after resistance training; Group C was given placebo 300ml one hour before and immediately after resistance training. Prior to the start of the experiment, participants were given dietary education (recommended dietary structure is 10-20% protein, 50-65% carbohydrate, and 20-30% fat). Participants completed diet records for 3 days (2 working days and 1 rest day) before intervention.

Intervention：

Study 1 recruited 10 male fitness enthusiasts from Beijing Sport University, aged 18-24 years old. Before the intervention, health examination was carried out to eliminate disturbing factors. The age, sex, medical history, health status, physical activity level and daily diet of the subjects were investigated by questionnaire, and informed consent was signed. The subjects were randomly divided into whey protein group (group W, n=5) and control group (group C, n=5) in a randomized cross-over double-blind experiment. After one intervention, group W and group C exchanged supplements for another intervention, during which they were eluted for 7 days. The action mode of acute resistance exercise is squat and bench press with barbell. Subjects were asked to squat at the same level as the femoral trochanter and knee joint, then fully extend the knee, bench press subjects were asked to drop the bar to touch the upper chest, and lift the elbow joint fully straight. The exercise training load follows the guidelines established by the American Strength and Conditioning Association, and a 1RM test is performed prior to the intervention in order to determine the intensity of the intervention in subsequent subjects. The specific training plan is as follows: ① Preparation activity: Repeat the 50% 1RM squat and bench press 8-10 times each, then rest for 60 s. ② The order of resistance exercise is to complete the squat first and then the bench press. The first 4 groups of squat load was 70% 1RM, each group repeated 8 times, rest between groups 60s; After the completion of the fourth group, rest 90s, and then complete the four sets of squat with a load of 50% 1RM. The first and second groups are repeated 8 times each, and the third and fourth groups are repeated until they cannot be completed (if the third group is exhausted, there is no need to do the fourth group). The rest between the groups is 60 s, and the fourth group is finished with a rest of 150 s. Then the movement was changed, and the load was 70% 1RM bench press 4 groups, each group repeated 8 times, and the rest between the groups was 60 s; After the completion of group 4, rest for 90 s, and then complete the bench press 4 sets at 50% 1RM, and repeat 8 times in groups 1 and 2, and repeat in groups 3 and 4 until they cannot be completed (if group 3 is exhausted, do not do group 4). In addition, the nutritional supplement program was as follows: Group W supplemented 1 bottle of Pinku protein product (300ml) 1 hour before and immediately after resistance training; Group C was given placebo 300ml one hour before and immediately after resistance training. Prior to the start of the experiment, participants were given dietary education (recommended dietary structure is 10-20% protein, 50-65% carbohydrate, and 20-30% fat). Participants completed diet records for 3 days (2 working days and 1 rest day) before intervention.

Intervention：

In the second study, 28 college students (14 male and 14 female) were recruited from Beijing Sport University. Before the intervention, health examination was carried out to eliminate interfering factors. The age, gender, medical history, health status, physical activity level and daily diet of the subjects were investigated by questionnaire, and informed consent was signed. Basic information, as well as body shape, body composition, and physiological function, was collected one week before the intervention. In a randomized controlled experiment, subjects were randomly divided into liquid whey protein group (group W, n=14) and blank control group (group C, n=14). All subjects underwent resistance training 4 times a week for 8 weeks. The changes of body shape, body composition index and physiological function were measured at 4 and 8 weeks after intervention. Elbow venous blood was collected before the first training, immediately after training, and 2 hours after training. Elbow venous blood was collected before, immediately after and 2 hours after the last training in week 8. Participants performed an eight-week resistance training intervention four times a week, with hip and leg training on Mondays and Fridays, chest and shoulder training on Wednesdays and Saturdays, and rest on Tuesdays and Sundays. Hip leg training includes squat, hard pull, sitting machine leg flexion and sitting machine leg bend four exercises, chest and shoulder training includes flat bench press, flat dumbbell bird, sitting dumbbell press and dumbbell bend four exercises. The subjects conduct movement exercises under the guidance of professional coaches to ensure the standardization of movements. Exercise training load follows the guidelines established by the American Strength and Conditioning Association, and a 1RM test is performed before the intervention to determine the intensity of the intervention in subsequent subjects. In week 1-2, subjects performed 5 sets of 10-12 RM for each movement, with an interval of 2-3 min between the groups. At week 3-4, the same action was performed in 5 groups, 8-10 RM per group, with an interval of 1-2 min between the groups. In the 5th to 8th week, the same action was performed in 5 groups, 6-8RM for each group, with an interval of 1-2 min between the groups. Update 1RM test every two weeks. In addition, the nutritional supplement plan was as follows: Group W immediately added 300ml of Pinku protein products after exercise on training day, and group C immediately added 300ml of placebo after exercise on training day. Prior to the start of formal nutritional supplementation, subjects were given dietary education (recommended dietary structure is 10-20% protein, 50-65% carbohydrate, and 20-30% fat). Participants completed diet records for 3 days (2 working days and 1 rest day) each week before and after the intervention.

Intervention：

In the second study, 28 college students (14 male and 14 female) were recruited from Beijing Sport University. Before the intervention, health examination was carried out to eliminate interfering factors. The age, gender, medical history, health status, physical activity level and daily diet of the subjects were investigated by questionnaire, and informed consent was signed. Basic information, as well as body shape, body composition, and physiological function, was collected one week before the intervention. In a randomized controlled experiment, subjects were randomly divided into liquid whey protein group (group W, n=14) and blank control group (group C, n=14). All subjects underwent resistance training 4 times a week for 8 weeks. The changes of body shape, body composition index and physiological function were measured at 4 and 8 weeks after intervention. Elbow venous blood was collected before the first training, immediately after training, and 2 hours after training. Elbow venous blood was collected before, immediately after and 2 hours after the last training in week 8. Participants performed an eight-week resistance training intervention four times a week, with hip and leg training on Mondays and Fridays, chest and shoulder training on Wednesdays and Saturdays, and rest on Tuesdays and Sundays. Hip leg training includes squat, hard pull, sitting machine leg flexion and sitting machine leg bend four exercises, chest and shoulder training includes flat bench press, flat dumbbell bird, sitting dumbbell press and dumbbell bend four exercises. The subjects conduct movement exercises under the guidance of professional coaches to ensure the standardization of movements. Exercise training load follows the guidelines established by the American Strength and Conditioning Association, and a 1RM test is performed before the intervention to determine the intensity of the intervention in subsequent subjects. In week 1-2, subjects performed 5 sets of 10-12 RM for each movement, with an interval of 2-3 min between the groups. At week 3-4, the same action was performed in 5 groups, 8-10 RM per group, with an interval of 1-2 min between the groups. In the 5th to 8th week, the same action was performed in 5 groups, 6-8RM for each group, with an interval of 1-2 min between the groups. Update 1RM test every two weeks. In addition, the nutritional supplement plan was as follows: Group W immediately added 300ml of Pinku protein products after exercise on training day, and group C immediately added 300ml of placebo after exercise on training day. Prior to the start of formal nutritional supplementation, subjects were given dietary education (recommended dietary structure is 10-20% protein, 50-65% carbohydrate, and 20-30% fat). Participants completed diet records for 3 days (2 working days and 1 rest day) each week before and after the intervention.