Resistance training in water Flashcards
Land vs water exercise (5)
- Directional resistance
- Muscular actions
- Movements
- Changes in direction
- Energy Expenditure
Land vs water: Directional resistance
Land
- Unidirectional
- Resistance is the force of gravity
Water
- Multidirectional
- resistance is the water-in opposite direction of the movement relative to the water, regardless of body position
- Allows us to work lesser-used/weaker muscles
- requires core stabilization throughout workout
Land vs water: Muscular actions
Land
- Concentric is ONE direction
- Work one muscle group during a single exercise
- TWO exercises needed to work opposing muscle groups
Water
- Concentric in BOTH directions
- Works opposing muscle groups in a single exercise
- Allows for muscle balance/symmetry
Land vs water: Movements
Land
- More jerky and less controlled
- Increase risk of injury due to speed of movement
Water
- Slower and smoother actions with greater control
- Decreased risk of injury due to increased control (harder to train power)
Land vs water: Changes in direction
Land:
- Air provides less resistance than water
- We are more agile on land
Water:
- water more resistant than air
- we are less agile in the water
(sudden changes in direction more difficult (core activation required)
(careful planning of choreography is required)
Land vs water: Energy expenditure
No valid research to suggest that effectively planned water based fitness programs are less effective at producing aerobic fitness benefits similar to land based fitness programs
how long must water based fitness programs be?
at least 6 - 12 weeks long, and include appropriate exercise intensity and progression
who benefits from exercise in water? (5)
- athletes - activity specific movements in a safe environment
- youth through older adult populations
- rehabilitation patients
- persons with disabilities
- pre- and post-natal
What are the Properties of water? (5)
- resistance
- turbulence
- thermal conductivity
- buoyancy
- hydrostatic pressure
- Resistance
- Water provides 12 times more resistance than air
- density of water 1000 times greater than air
- resistance depends on surface area, speed of movement and ROM
- Changes in resistance are accomplished by altering these three factors, 1. surface area. 2. speed, 3. ROM
- Resistance, what to alter to change resistance (3 factors)
- surface area: increase surface area to make water resistance harder
- lever length
- configuration of hands and feet - Speed: move faster to increase resistance and speed of ROM
- Range of Motion:
- work = force x distance
- increased ROM increases workload and energy cost
- Turbulence
- Movement can be adjusted to produce laminar or turbulent flow.
- More streamlined = greater ease of movement (and laminar flow)
- High pressure zone in front of moving body and lower pressure zone in rear - this movement causes turbulent flow
- Thermal Conductivity
water conducts heat away from body about 25 times faster than air, pool water generally warmer than room temp, heat produced by working muscles is transferred to skin via blood and dissipated efficiently by thermal conductivity of water
- temp of pool and air affect exercise design
cool pool
cool pool = spend more time warming up, include lots of movement to stay warm, spend less time cooling down
- Buoyancy
- Counter-balances the force of gravity, more surface area = more float
- Depth of immersion, body density, volume and lung capacity affect buoyancy
- muscle has greater density than fat
-filling lungs with air increases buoyancy - larger object has greater displacement of water
- Buoyancy gravitational pull
gravitational pull (downward_ reduced by 43% when submerged to the neck, 29% when submerged to the xiphoid process, and 15% when submerged to the hip
Buoyancy is good for population groups including, obese, elderly, athletic, disabled, pre/post-natal
why?
- decreased effect of gravity reduces amount of shock transmitted through bones, joints and ligaments
- decreased joint loading contributes to an increase in ROM of joints
- can result in improved joint mobility and resistance to joint injury
- special populations can exercise in relative comfort and ease
- Hydrostatic pressure
- Water exerts pressure against the body-increases depth of immersion
- This pressure reduces the gravitational pull on the circulatory system
- assists with venous return which helps recovery by increasing blood to heart
- increased filling of heart: heart becomes more efficient pump= heart rate lower even at a given work load
- Increased blood flow to heart causes lower blood pressure
How does hydrostatic pressure allow better mobility, circulation and healing?
reduces edema (swelling) of injured joints and limbs
hydrostatic pressure affect of workload respiratory system
workload respiratory system increases
- pressure on submerged thoracic cavity reduces expiratory volume from 1.5L to less than 1L
- Vital capacity is reduced by about 10 percent
AQUATIC HEART RATE
- Water based heart rates are LOWER than land based heart rates, due to:
1. Thermal conductivity: dissipates heat with less strain on circulatory system
2. Buoyancy: Lessened effect of gravity
3. Hydrostatic pressure: compression on veins and arteries facilitates blood flow
4. Partial pressure: Gases enter liquids more easily under pressure
Aquatic heart rate in horizontal position relative to vertical?
heart rate while in horizontal position is even lower than while vertical
Aquatic heart rate: How much lower is our exercise heart rate?
- rough estimate exercise HR’s in water approximately 13% lower than on land
- using estimate, our recommendation would still be to achieve an intensity between 65 and 90% of MHR
