Tag: functional fitness

  • Cable Machine Workouts After 40: Strength & Stability

    Cable Machine Workouts After 40: Strength & Stability

    Cable Machine Workouts After 40: Strength & Stability

    One of the most versatile pieces of gym equipment may also be the most underused by adults in midlife — and the science behind it is compelling.

    Why Adults Over 40 Should Take Cable Machines Seriously

    Mark, 52, had spent years avoiding the cable machine at his gym. It looked complicated, and he assumed it was mostly for bodybuilders. But after his physical therapist recommended cable-based exercises to help rehabilitate his rotator cuff and protect his lower back, everything changed. Within three months, he was moving with less pain, standing taller, and lifting with more confidence than he had in his 30s.

    If you’re over 40 and focusing on long-term health, you’ve probably already heard that strength training is essential. According to the CDC, adults begin losing 3 to 5 percent of muscle mass per decade after age 30 — a process called sarcopenia — and that rate accelerates without resistance training. But not all strength training is created equal, especially as your joints, connective tissue, and recovery capacity change with age.

    Cable machine workouts offer a unique combination of constant resistance, joint-friendly movement, and functional carry-over to real life. In this guide, you’ll learn what cable machines are, why they’re particularly beneficial after 40, how to use them safely, and how to build a complete workout routine that supports your strength, stability, and longevity goals.

    What Is a Cable Machine?

    A cable machine is a piece of gym equipment that uses a system of pulleys, cables, and adjustable weight stacks to create resistance throughout the full range of motion of an exercise. Unlike free weights — where resistance changes based on gravity — cable machines maintain tension on your muscles from start to finish of each movement.

    Most gyms offer two main types: a single-cable tower with an adjustable pulley (high, mid, or low position) and a functional trainer, which features two independent cable arms that can be set at different heights. Both allow for dozens of exercises targeting nearly every major muscle group.

    According to research published in the Journal of Strength and Conditioning Research, cable-based resistance training activates stabilizing muscles more consistently than machine-based exercises that isolate movement on a fixed track. This makes cables particularly valuable for adults over 40 who want to build real-world functional strength — not just isolated muscle size.

    Why Cable Machines Are Especially Beneficial After 40

    After 40, several physiological shifts make certain training approaches more appropriate than others. Your tendons and ligaments are less elastic than they were in your 20s, joint cartilage may show early wear, and your nervous system’s ability to recover from intense training takes longer. Cable machines address many of these concerns directly.

    Constant tension without joint compression. Unlike barbell squats or heavy bench presses, many cable exercises reduce axial loading (downward compression on the spine and joints) while still providing significant muscular challenge. This is especially helpful if you manage conditions like osteoarthritis, a herniated disc, or shoulder impingement.

    Improved neuromuscular coordination. Because cables require you to stabilize the movement path yourself — rather than following a fixed machine track — they engage your core and stabilizing muscles simultaneously. Clinical evidence from rehabilitation studies at the Mayo Clinic suggests this co-activation pattern improves balance, coordination, and injury resilience over time.

    Adjustable angles for joint-friendly movement. The pulley height is fully adjustable, which means you can modify the angle of resistance to match your individual joint mechanics. If traditional rows hurt your shoulder in one position, you can shift the cable angle slightly until the movement feels comfortable and productive.

    Lower injury risk than free weights for beginners. Research suggests that cable exercises have a lower rate of acute injury for adults returning to training after a break, making them an excellent starting point if you’ve been sedentary or are returning from injury.

    Key Muscle Groups and Cable Exercises to Know

    One of the greatest strengths of the cable machine is its versatility. Here’s a breakdown of major muscle groups and the cable exercises most clinically relevant for adults over 40:

    Back and Posterior Chain

    • Cable rows (seated or standing): Target the latissimus dorsi, rhomboids, and rear deltoids. Excellent for counteracting the forward-rounded posture that develops from prolonged sitting.
    • Face pulls: Specifically strengthen the rear deltoids and rotator cuff — two areas critical for shoulder health and often underdeveloped in adults over 40.
    • Cable pull-throughs: A hip-hinge movement that activates the glutes and hamstrings with minimal spinal compression, making it a safer alternative to deadlifts for those with lower back sensitivity.

    Chest and Shoulders

    • Cable chest fly (low-to-high or high-to-low): Provides constant pectoral tension without the shoulder strain of heavy dumbbell flyes.
    • Lateral raises: Cable lateral raises maintain tension at the top of the movement where dumbbells go slack, improving shoulder development and rotator cuff resilience.

    Core and Stability

    • Pallof press: An anti-rotation core exercise considered by many sports medicine clinicians to be one of the safest and most effective core stability movements available. It trains your core to resist force — exactly what it needs to do to protect your spine in daily life.
    • Cable woodchops: Rotational core training that mimics reaching, lifting, and twisting movements common in daily activities.

    Legs and Glutes

    • Cable kickbacks: Isolate the glutes with minimal knee stress.
    • Cable Romanian deadlifts: Hip-hinge movement that strengthens the hamstrings and glutes through a long range of motion.
    • Cable squats: A counterbalanced squat variation that allows upright posture and is often more accessible for adults with limited hip mobility.

    Arms

    • Cable bicep curls and tricep pushdowns: Classic movements with consistent tension throughout the full range — more effective for muscular endurance than many free-weight equivalents.

    How to Build a Cable Machine Workout Routine After 40

    Most fitness professionals and sports medicine physicians recommend that adults over 40 train 2 to 4 days per week with at least one full rest day between sessions targeting the same muscle groups. Here is a sample two-day split designed for longevity, functional strength, and joint health.

    Day 1 — Upper Body Focus (45-55 minutes)

    Begin with a 5-minute warm-up: arm circles, shoulder rolls, and light band pull-aparts.

    • Face pulls — 3 sets x 15 reps (light to moderate weight)
    • Seated cable rows — 3 sets x 10-12 reps
    • Cable chest fly (low-to-high) — 3 sets x 12 reps
    • Cable lateral raises — 3 sets x 12-15 reps per side
    • Cable bicep curls — 3 sets x 12 reps
    • Tricep pushdowns — 3 sets x 12 reps
    • Pallof press — 3 sets x 10 reps per side (slow and controlled)

    Day 2 — Lower Body and Core Focus (45-55 minutes)

    Begin with a 5-minute warm-up: hip circles, bodyweight squats, and standing cat-cow stretches.

    • Cable pull-throughs — 3 sets x 12 reps
    • Cable squats — 3 sets x 10-12 reps
    • Cable Romanian deadlifts — 3 sets x 10 reps
    • Cable kickbacks — 3 sets x 15 reps per leg
    • Cable woodchops (high-to-low) — 3 sets x 10 reps per side
    • Standing cable crunches — 3 sets x 12 reps

    Rest 60 to 90 seconds between sets. Research suggests that longer rest periods (up to 2 minutes) are appropriate for adults over 40 when training at moderate to high intensity, as this improves recovery quality and reduces the risk of overuse injuries.

    Safety Tips and Common Mistakes to Avoid

    Cable machines are generally safe, but proper form and progression matter enormously — especially after 40 when connective tissue takes longer to adapt than muscle tissue does.

    Start lighter than you think you need to. This is the most common mistake among adults returning to resistance training. Clinical guidelines from the American College of Sports Medicine recommend starting at 40 to 60 percent of your estimated maximum load and progressing gradually over weeks — not days.

    Prioritize control over speed. A slow, controlled eccentric phase (the lowering or releasing portion of each rep) has been shown in multiple meta-analyses to significantly improve muscle quality and reduce injury risk. Aim for a 2 to 3 second lowering phase on every repetition.

    Adjust the pulley before loading it. Always adjust the pulley height before adding weight or attaching cables. Reaching awkwardly while under tension is a common cause of shoulder and wrist strain.

    Avoid locking out joints under heavy load. Particularly with elbow and knee joints, maintain a slight soft bend at the end range of motion to reduce joint stress.

    Don’t skip the warm-up. A 5 to 10 minute dynamic warm-up is non-negotiable after 40. According to Johns Hopkins Medicine, warming up increases blood flow to muscles, improves nerve conduction speed, and meaningfully reduces injury risk during resistance training.

    You may also find it helpful to complement your cable training with low-impact cardio on alternate days. If you’re looking for joint-friendly cardio options that pair well with strength training, our guides on elliptical workouts after 50 and rowing machine workouts after 40 offer detailed, age-appropriate programs worth exploring.

    Living With Chronic Conditions: Adapting Cable Training Safely

    Many adults over 40 are managing at least one chronic condition — and that shouldn’t be a barrier to cable training. In fact, research suggests resistance training is actively beneficial for several of the most common conditions in this age group.

    Osteoarthritis: The Arthritis Foundation recommends resistance training as a primary non-pharmacological treatment for osteoarthritis. Cable exercises reduce joint impact while preserving the resistance needed to maintain cartilage-supporting muscle strength. Focus on mid-range movements and avoid deep end-range positions that cause pain.

    Type 2 diabetes: According to the American Diabetes Association, resistance training improves insulin sensitivity and blood glucose regulation. Cable-based workouts two to three times per week may complement your diabetes management plan — always in coordination with your physician.

    Hypertension: The American Heart Association supports moderate-intensity resistance training for adults with controlled hypertension. Avoid breath-holding (Valsalva maneuver) during cable exercises, as this temporarily spikes blood pressure. Breathe steadily and continuously throughout each rep.

    Lower back pain: Cable exercises like the Pallof press, cable pull-throughs, and standing cable rows are frequently prescribed in physical therapy settings for lumbar stabilization. If you have a diagnosed back condition, consult your physician or physical therapist before beginning.

    For those who prefer to mix equipment-based and bodyweight work, our guide to home workouts for adults over 50 offers a complementary framework that pairs well with cable training days at the gym.

    When to Talk to Your Doctor or Skip the Gym

    While cable machine training is appropriate for most healthy adults over 40, there are situations where medical clearance or a modified approach is essential.

    Seek medical clearance before starting if you:

    • Have been sedentary for more than 12 months
    • Have a cardiovascular condition, including recent heart attack, arrhythmia, or uncontrolled hypertension
    • Have been diagnosed with osteoporosis (not osteopenia — osteoporosis requires specific exercise guidance)
    • Are recovering from surgery or a musculoskeletal injury in the past 6 months
    • Experience chest pain, dizziness, or shortness of breath during physical activity

    Stop immediately and seek emergency care if during exercise you experience:

    • Chest pain, pressure, or tightness
    • Sudden severe shortness of breath not explained by exertion
    • Jaw, arm, or back pain occurring with exertion
    • Sudden dizziness, near-fainting, or loss of coordination
    • A sharp, severe pop or snap in a joint followed by significant pain or swelling

    These symptoms require immediate emergency evaluation. Do not wait to see if they resolve on their own.

    At your next routine visit, consider discussing:

    • Whether your current medications affect exercise capacity or heart rate response
    • Baseline labs relevant to muscle health (vitamin D, magnesium, creatinine)
    • A referral to a physical therapist or certified personal trainer with experience in older adult fitness

    Frequently Asked Questions

    Can I use a cable machine if I’ve never lifted weights before?
    Yes — cable machines are often considered more beginner-friendly than free weights because the cable guides your movement path and reduces the coordination demand. Starting with a certified personal trainer for 2 to 3 sessions to learn proper setup and form is strongly recommended, especially after 40.

    How is cable training different from using weight machines?
    Weight machines (like a chest press or leg extension machine) fix you into a single movement plane and do much of the stabilization work for you. Cable machines require your stabilizing muscles to engage throughout, which builds more functional, transferable strength. Research suggests this makes cables more effective for improving real-world movement quality.

    How much weight should I start with on a cable machine?
    This varies significantly from person to person and depends on the exercise, your training history, and your current fitness level. A general guideline from the American College of Sports Medicine is to select a weight that allows you to complete 12 to 15 reps with good form while feeling challenged on the last 2 to 3 reps. Never sacrifice form to use more weight.

    Is cable training safe if I have shoulder problems?
    For many common shoulder issues — including rotator cuff strain and shoulder impingement — cable exercises are frequently prescribed in physical therapy because of their adjustable angles and controlled resistance. However, you should get a diagnosis and personalized guidance from your orthopedic physician or physical therapist before training through shoulder pain.

    How long before I see results from cable machine workouts?
    Clinical evidence indicates that most adults begin noticing improvements in strength, posture, and ease of daily movement within 4 to 6 weeks of consistent training (2 to 3 sessions per week). Visible changes in muscle definition typically take 8 to 12 weeks. Individual variation is significant and depends on nutrition, sleep, stress, and consistency.

    Conclusion: The Smarter Strength Tool for the Second Half of Life

    Cable machines aren’t just for athletes or bodybuilders. For adults over 40, they represent one of the most intelligent, joint-friendly, and functional tools available in any gym. They deliver constant resistance, engage stabilizing muscles, reduce injury risk, and adapt to your body’s specific mechanics — all qualities that matter enormously as you prioritize longevity over performance.

    Whether you’re managing a chronic condition, returning to exercise after a break, or simply looking to train smarter as you age, cable-based workouts offer a sustainable path to better strength, posture, balance, and quality of life. Start gradually, focus on form, and build the habit consistently.

    As always, partner with your physician or a qualified fitness professional to create a plan that’s right for your individual health needs. The investment you make in your strength today pays dividends in independence, vitality, and resilience for decades to come.

    For more age-appropriate strength and fitness ideas, explore our guide to dumbbell workouts for adults over 40 as a complement to your cable training routine.


    Medical Disclaimer: This article is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment. Always consult your physician or a qualified healthcare provider before making changes to your health routine or treatment plan.

    Medically reviewed by our editorial health team. Content follows evidence-based standards aligned with CDC and NIH guidelines.

  • Functional Fitness After 50: Move Better, Live Stronger

    Functional Fitness After 50: Move Better, Live Stronger

    The exercises that help you carry groceries, climb stairs, and get up from the floor without pain — and how to start doing them today.

    Introduction

    Margaret, 63, had been hitting the treadmill three times a week for years. She looked fit. But when she tried to lift a heavy bag from an overhead bin during a flight, she pulled a muscle in her shoulder. "I thought I was in shape," she told her physical therapist. "Turns out I was fit for the gym — but not for real life."

    Margaret’s story is more common than most people realize. According to the CDC, adults over 50 are among the fastest-growing segments of the US population, and physical function — the ability to perform everyday activities without pain or limitation — is one of the strongest predictors of long-term health and independence.

    Functional fitness is an approach to exercise specifically designed to train your body for real-life movements: bending, reaching, pushing, pulling, twisting, and carrying. It’s not about lifting the heaviest weight or running the fastest mile. It’s about building the strength, balance, and mobility that make daily life easier and safer.

    In this guide, you’ll learn what functional fitness is, why it matters so much after 50, and how to build a safe, effective routine — even if you haven’t exercised in years.

    What Is Functional Fitness?

    Functional fitness refers to exercise that trains your muscles and joints to work together in ways that mirror real-world movements. Rather than isolating a single muscle on a machine, functional training uses compound movements — exercises that recruit multiple muscle groups simultaneously.

    Think about what you do every day: getting up from a chair, picking something up off the floor, pushing open a heavy door, carrying a laundry basket. Each of these actions requires coordination, balance, and strength from several body parts working in sync. Functional fitness trains exactly those patterns.

    According to the National Institute on Aging (NIA), a branch of the NIH, maintaining physical function is a primary goal of healthy aging — and functional movement training is one of the most evidence-supported ways to achieve it.

    This approach is especially powerful for adults over 50 because it simultaneously addresses the four pillars of physical health that tend to decline with age: strength, balance, flexibility, and endurance.

    Why Functional Fitness Matters More After 50

    Starting around age 30, adults begin losing muscle mass at a rate of approximately 3 to 5 percent per decade — a process called sarcopenia. After 50, that loss can accelerate if not actively countered through resistance-based movement.

    The consequences go far beyond aesthetics. Loss of muscle and functional strength is directly linked to increased fall risk, reduced mobility, greater dependence on others, and higher rates of chronic disease. The CDC reports that falls are the leading cause of injury-related death among Americans over 65, with 3 million older adults treated in emergency departments for fall injuries each year.

    Functional fitness addresses this risk at its root. By training the muscles and movement patterns that stabilize the body during daily activities, it builds the kind of resilience that keeps you independent, confident, and mobile well into your later decades.

    Research published in the Journal of Aging and Physical Activity found that older adults who engaged in functional resistance training showed significant improvements in walking speed, balance, and self-reported quality of life compared to those doing traditional machine-based exercise. This variation in outcomes is well-documented — individual results depend on baseline fitness, health conditions, and consistency.

    Key Functional Movement Patterns to Train

    Functional fitness is built around six foundational movement patterns. Training all six ensures your body is prepared for the full range of activities daily life demands.

    1. Squat (sitting and standing)
    The squat pattern mirrors getting up from a chair or a toilet. It trains your quadriceps, glutes, hamstrings, and core. For beginners, a chair squat — standing up from a seated position and slowly lowering back down — is a safe, effective starting point.

    2. Hinge (bending forward)
    The hip hinge mimics picking something up off the floor or loading the dishwasher. It trains the posterior chain — the glutes, hamstrings, and lower back. A Romanian deadlift with light dumbbells or a resistance band is a classic hinge exercise that most adults can learn safely.

    3. Push (pushing away from the body)
    Pushing movements train the chest, shoulders, and triceps. Wall push-ups or tabletop push-ups are excellent low-impact starting points for adults who haven’t trained upper body strength in a while.

    4. Pull (pulling toward the body)
    Pulling trains the upper back, biceps, and rear shoulders — muscles critical for posture and carrying. Resistance band rows are an approachable, joint-friendly option. If you’re interested in band-based training, our guide on Resistance Band Workouts: Strength & Mobility for All Ages offers a detailed introduction.

    5. Carry (moving while holding a load)
    Farmer’s carries — simply walking while holding a weight in each hand — build grip strength, core stability, and upright posture. They train the body exactly as grocery shopping does.

    6. Rotation (twisting)
    Rotational movements train the obliques and thoracic spine, preparing you for tasks like reaching across your body or looking over your shoulder while driving. Standing torso rotations with a light medicine ball or just bodyweight are safe starting points.

    A Sample Functional Fitness Routine for Adults Over 50

    Clinical evidence suggests that most adults over 50 benefit from at least two to three days of strength-focused functional training per week, with rest days or gentle movement — like walking or stretching — in between. The American College of Sports Medicine (ACSM) recommends that older adults perform muscle-strengthening activities on two or more days per week.

    Here is a beginner-to-intermediate weekly structure:

    Day 1 — Lower Body & Core Stability

    • Chair squats: 3 sets of 10–12 reps
    • Romanian deadlift with dumbbells or band: 3 sets of 10 reps
    • Standing calf raises: 3 sets of 15 reps
    • Dead bug (core stability): 3 sets of 8 reps per side
    • Side-lying hip abduction: 2 sets of 12 reps per side

    Day 2 — Upper Body & Posture

    • Wall push-ups or incline push-ups: 3 sets of 10–12 reps
    • Resistance band rows: 3 sets of 12 reps
    • Band pull-aparts: 3 sets of 15 reps
    • Overhead reach with band: 3 sets of 10 reps
    • Farmer’s carry: 3 rounds of 30 steps

    Day 3 — Balance, Mobility & Full-Body Integration

    • Single-leg stance: 3 sets of 30 seconds per side
    • Step-ups onto a low platform: 3 sets of 10 reps per leg
    • Lateral band walks: 3 sets of 12 steps per direction
    • Standing torso rotations: 3 sets of 10 per side
    • Hip flexor stretch (kneeling or standing): 2 sets of 30 seconds per side

    Always warm up for 5 to 10 minutes with gentle walking or light movement before beginning any strength work. Cool down with static stretching, focusing on the muscle groups you trained. If you’re also interested in structured low-impact options to complement this routine, you may find our article on Water Aerobics After 50: Benefits, Safety & How to Start a useful pairing for cardiovascular fitness.

    Safety: What to Know Before You Start

    Functional fitness is designed to be accessible — but that doesn’t mean it’s completely without risk, especially if you have existing health conditions. Research suggests that most exercise-related injuries in older adults result not from exercise itself, but from doing too much, too soon, without proper form.

    Here are the most important safety principles for adults over 50 starting a functional fitness program:

    • Get medical clearance first. If you have cardiovascular disease, osteoporosis, joint replacement, or uncontrolled hypertension, consult your physician before beginning a new exercise routine. Most doctors strongly support functional training — but your specific health history matters.
    • Start with bodyweight or very light resistance. Mastering movement form before adding load protects your joints and reduces injury risk significantly.
    • Prioritize form over speed or weight. Slow, controlled repetitions are more effective and far safer than rushing through exercises.
    • Listen to pain signals. Muscle fatigue is expected. Sharp, joint, or radiating pain is a warning sign to stop and evaluate.
    • Rest and recover. Muscle repair happens during rest. Adequate sleep supports your training outcomes — something our guide on Better Sleep After 50: Causes, Tips & When to See a Doctor covers in depth.
    • Consider working with a certified personal trainer or physical therapist at least initially. A professional can assess your movement quality and correct imbalances before they lead to injury.

    When to Call Your Doctor or Seek Emergency Care

    Most functional fitness discomforts — mild muscle soreness, slight fatigue, minor stiffness — are normal and resolve within 24 to 72 hours. However, some symptoms during or after exercise require immediate attention.

    Seek emergency care immediately if you experience:

    • Chest pain, pressure, or tightness during or after exercise
    • Severe shortness of breath that doesn’t resolve quickly with rest
    • Dizziness, lightheadedness, or fainting
    • Heart palpitations or an irregular, racing heartbeat
    • Sudden, severe joint or muscle pain (which may indicate a tear or fracture)
    • Numbness, tingling, or weakness radiating down an arm or leg

    Schedule a non-emergency appointment with your doctor if you notice:

    • Joint swelling that persists more than 48 hours after exercise
    • Persistent pain that worsens over multiple training sessions
    • Unusual fatigue that doesn’t improve with rest
    • Any new symptom that concerns you, even if it seems minor

    The American Heart Association recommends that adults with known cardiovascular risk factors discuss their exercise plans with a physician before significantly increasing activity intensity.

    Frequently Asked Questions

    Q: Is functional fitness the same as physical therapy?
    A: They share many exercises and principles, but they’re not the same. Physical therapy is a medically supervised rehabilitation process for specific injuries or conditions. Functional fitness is a preventive and performance-based training approach for generally healthy adults. That said, many physical therapists incorporate functional movement principles into their programs — and many people transition from PT to functional fitness training after recovering from an injury.

    Q: How soon will I see results from functional fitness training?
    A: This varies from person to person, but clinical evidence suggests that most adults begin noticing improvements in strength, balance, and daily ease of movement within four to eight weeks of consistent training. Neurological adaptations — how efficiently your brain coordinates movement — can occur even faster, often within the first two to three weeks.

    Q: Can I do functional fitness if I have osteoporosis?
    A: Research suggests that weight-bearing and resistance exercise can be beneficial for bone density, even in people with osteoporosis. However, certain movements — such as deep forward bends or high-impact jumps — may need to be modified or avoided. A physician or physical therapist familiar with osteoporosis should guide your specific program before you begin.

    Q: Do I need any equipment to start?
    A: No. Many of the most effective functional exercises require only your bodyweight — chair squats, wall push-ups, single-leg stands, and farmer’s carries with household objects. As you progress, a pair of light dumbbells and one or two resistance bands significantly expand your options at minimal cost.

    Q: How does functional fitness compare to yoga or Pilates?
    A: All three approaches complement each other well. Functional fitness emphasizes strength and movement pattern training. Yoga targets flexibility, breath, and mind-body connection. Pilates focuses on deep core stability and postural alignment. For many adults over 50, combining functional fitness with yoga or Pilates — on alternating days — offers the broadest physical benefits. Our articles on Yoga for Adults Over 40 and Pilates After 40: Core Strength, Posture & Pain Relief explore those approaches in detail.

    Conclusion

    Functional fitness isn’t a trend — it’s a smarter way to think about what exercise is actually for. After 50, the goal isn’t just to look fit. It’s to feel capable, move confidently, and maintain the independence that makes life meaningful.

    The good news is that the research is clear: it’s never too late to start. Even adults who begin functional training in their 60s or 70s show meaningful improvements in strength, balance, and quality of life. You don’t need a gym membership or a complicated program. You need consistent, purposeful movement that prepares your body for the life you want to live.

    Talk to your doctor, start with what you can do today, and build from there. Your future self — the one who carries their own groceries, climbs stairs without holding the rail, and gets up from the floor with ease — will thank you.


    Medical Disclaimer: This article is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment. Always consult your physician or a qualified healthcare provider before making changes to your health routine or treatment plan.

    Medically reviewed by our editorial health team. Content follows evidence-based standards aligned with CDC and NIH guidelines.