The exercise programs were planned according to the principles of the ACSM1 (1990, 1998a) recommendations. The intensity of the exercise was planned to be light to moderate; 45% VO2max, 55% VO2max or 65% VO2max. The lowest intensity was approximately the minimum intensity of the recommendation and the highest intensity was moderate. The weekly exercise volume was set at 1500 kcal or 1000 kcal, which should be at the lowest border of effective exercise to influence cardiovascular risk according to ACSM (1998a), Hambrecht (1993) and the Ontario symposium (Kesäniemi 2001). The frequency of exercise was chosen to be five d⋅wk-1, which is more frequent than the minimum requirement of the recommendation, in order to keep the exercise duration feasible. The daily training was continuous in groups E1, E3, E4, E5, and E6 and two equally long sessions with at least a 5-hour interval in group E2 in order to test the fractionization of exercise. Walking was considered the most common and most feasible form of sustainable dynamic aerobic exercise for sedentary women and was chosen as the mode of exercise (Morris and Hardman 1997). The minimum recommended length for an intervention, 15 weeks, was chosen in Study I (ACSM 1998a). A longer length, 24 weeks, was chosen for Study II, because the smaller exercise doses were suspected to be slower to produce effects on the chosen variables.
The individual target heart rate, corresponding to 45% VO2max, 55% VO2max
or 65% VO2max, was determined for each participant in the first maximal exercise
1ACSM 1998:
Cardiorespiratory fitness and body composition:
1. Frequency of training: 3-5 d⋅wk-1.
2. Intensity of training: 55/65% of maximum heart rate or 40/50-85% of maximum oxygen uptake reserve (VO2R) or HRmax reserve (HRR). HRR and VO2R are calculated from the difference between resting and maximum heart rate and resting and maximum VO2, respectively. To estimate training intensity, a percentage of this value is added to the resting heart rate and/or resting VO2 and is expressed as a percentage of HRR or VO2R.
3. Duration of training: 20-60 min of continuous or intermittent (minimum 10 min bouts accumulated through the day) aerobic activity.
Muscular strength and endurance, body composition, and flexibility:
1. Resistance training: One set of 8-10 exercises that condition major muscle groups 2-3 d⋅wk-1, 8-12 repetitions of each exercise and for older persons over 50-60 years 10-15 repetitons may be more appropriate.
2. Flexibility training: These exercises should stretch the major muscle groups and be performed a minimum of 2-3 d⋅wk-1. Stretching should include appropriate static and/or dynamic techniques.
48
test. The duration of daily exercise corresponding to 300 kcal or 200 kcal was also calculated individually in the first maximal exercise test using the Weir formula2, which estimates energy expenditure (kcal ⋅ min-1) from measured oxygen consumption (L ⋅ min-1) and carbon dioxide production (L ⋅ min-1) (de Weir 1949) (Table 4).
Table 4. The exercise program prescribed for the exercise groups in Study I and Study II (standard deviation)* Frequency of training, sessions per
week
5 2 x 5 5 5 5 5
* E1-E2 = exercise groups in Study I, E3-E6 = exercise groups in Study II, BMI = body mass index, VO2max = maximal aerobic power
A short resistance training program was also used in groups E1 and E2 in Study I. It was planned according the minimum requirement of the ACSM recommendation (1990, 1998a), and was planned to be performed with as little equipment as possible (Figure 1).The resistance training program consisted of one set of eight moderate-intensity, dynamic exercises with 10 repetitions for each for the main muscle groups twice a week. Body weight or 2-5 kg dumbbells were used as resistance. Some of the exercises were also planned to have an effect on motor fitness, and also flexibility exercises were conducted. The program consisted of two exercises in a standing position for the leg muscles, balance and coordination (knees-up, back touch), one for hip and knee extensor muscles (squat), one for muscles of the upper arms using 2- or 5- kg dumbbells (dumbbell military press), two for back extensor muscles in the prone position,
2 Weir 1949:
Exercise energy expenditure (kcal⋅min-1) = (3.941 x VO2 (L⋅min-1))+ (1.106 x VCO2 (L⋅min-1))
49 two for the abdominal region (sit-ups straight and diagonally), followed by five subsequent stretching exercises. The duration of the muscular training bout was approximately 15 to 20 minutes.
Figure 1. Resistance training program used in Study I
Warm-up and to improve standing balance and body coordination
Exercise 1 Exercise 2
1) Knees-up in standing position with alternating legs 20 rep. (2 x 10+10 rep.) 2) Back touch in standing position with alternating legs 20 rep. (2 x 10+10 rep.)
Warm-up and enhancement of endurance of the trunk, legs and upper limb muscles
Exercise 3 Excersice 4
Excersise 5 Excersise 6
3) Dumbbell military press with alternating arms
20 rep. (2 x 10+10 rep.) with 2 to 5 kg weight
4) Squat exercise on two legs 10 rep.
5) Back extensor exercise on prone: Lifting opposite upper and lower limbs
10 rep. with 5 seconds hold
6) Upper body extensor exercise on prone 10 rep. with 5 seconds hold
50
Excercise 7
Excercise 8
7) Curl-ups on supine with alternating legs 10 rep.
8) Curl-ups and side bending on supine 20 rep. (2 x 10+10 rep.) for both sides
Recovery after aerobic exercise to increase the flexibility and to prevent musculoskeletal complaints
Excercise 9 Excercise 10 Excercise 11 Excercise 12 Excercise 13 9) Stretching exercise for hamstrings 30 seconds for each leg 10) Stretching exercise for pectoralis major 30 seconds for both sides 11) Stretching exercise for calf muscles 30 seconds for both legs 12) Stretching exercise for thoracic region 30 seconds
13) Stretching exercise (lateral bending) for neck muscles 30 seconds stretch for both side rep.= repetitions
51 Two of the weekly walking sessions were supervised by an exercise leader on an indoor track. These sessions included the resistance training program as a warm-up for walking in Study I. The other weekly walking sessions, three for Growarm-up E1, E3, E4, and E5 and eight for Group E2 were unsupervised and took place outdoors. A few minutes of light flexibility exercises of the participants' own choice were recommended before and after every session as a warm-up and cool-off and for injury prevention.
HR monitors (Polar Edge, Polar Electro, Kempele, Finland) were used as a means of controlling the HR in the two weekly supervised sessions and every third week in all weekly sessions. The participants were also advised to estimate the length of their walking route periodically, in order to keep the same relative pace in all weekly sessions. The duration of the exercise session with a prescribed target HR was registered in an exercise diary. In addition the participants wore pedometers (step counters) (Fitty 3, Kasper & Richter, Utrecht, Germany) for 3 days, from Friday to Sunday, in the middle of the intervention period.