Treatment group II will receive inspiratory muscle endurance training (IMT) using threshold loading device (POWERbreathe Classic, IMT Technologies Ltd. Birmingham, England) at 30% of maximal inspiratory pressure (MIP).

The MIP will be measured at supervised session each week, and 30% of measured MIP value will be the new training workload.

The treatment group will train for 30 min-per/day, 7 days/week, for 8 weeks. Six sessions at home and 1 session will be performed at department.

Spirometry

Fatigue Severity Scale (FSS) (Turkish version of scale) Patient choose a number from 1 to 7 that indicates how much the patient agrees with each statement, where 1 indicates strong disagreement and 7 indicates strong agreement. A score of 4 or higher generally indicates severe fatigue

Short Form (SF-36) Health Survey (Turkish version of scale) The SF-36 is a 36 item questionnaire that measures eight multi-item dimensions of health: physical functioning (10 items) social functioning (2 items) role limitations due to physical problems (4 items), role limitations due to emotional problems (3 items), mental health (5 items), energy/vitality (4 items), pain (2 items), and general health perception (5 items). For each dimension item scores are coded, summed, and transformed on to a scale from 0 (worst possible health state measured by the questionnaire) to 100 (best possible health state).

Montgomery Asberg Depression Rating Scale (MADRS) (Turkish version of scale) This assessment tool contains 10 items with a score from 0 to 6, thus the maximum score is 60. A higher score indicates a more severe depression.

International Physical Activity Questionnaire (IPAQ) - Short Form (Turkish version of scale ) This questionnaire assesses, in minutes, the physical activity performed by the volunteers during the period of one week. The IPAQ considered all activities carried out by the volunteer (e.g. leisure, sport, exercise, and activities at home or in the garden). According to the responses, the volunteer is considered very active, active, irregularly active or sedentary, according to the intensity and time of the exercises practiced over the last week.

Minnesota Living with Heart Failure Questionnaire (MLHFQ) (Turkish version of scale) 21 items rated on six-point Likert scales, representing different degrees of impact of HF on Heart Related Quality of Life (HRQoL), from 0 (none) to 5 (very much). It provides a total score (range 0-105, from best to worst HRQoL), as well as scores for two dimensions, physical (8 items, range 0-40) and emotional (5 items, range 0-25).

Mini mental state examination (MMSE)(Turkish version of scale ) The scale has a maximum score of 30 points. The questions have been grouped into seven categories, each rationally representing a different cognitive domain or function: Orientation to time (5 points); Orientation to place (5 points); Registration of three words (3 points); Attention and Calculation (5 points); Recall of three words (3 points); Language (8 points) and Visual Construction (1 point). The severity of cognitive impairment is classified as normal (30-27) mild cognitive impairment (26-20); moderate cognitive impairment (19-10); and severe cognitive impairment(< 10).

6 minute walking test